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Relevant bibliographies by topics / Cis-Hydrogenation

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Dissertations / Theses
Book chapters

Academic literature on the topic 'Cis-Hydrogenation'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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Journal articles on the topic "Cis-Hydrogenation"

1

Muchalal, Muchalal. "PARALLEL REACTION ON CATALYTIC HYDROGENATION REACTION OF CIS-ISOEUGENOL INTO 2-METHOXY-4-PROPYLPHENOL." Indonesian Journal of Chemistry 5, no. 2 (2010): 169–72. http://dx.doi.org/10.22146/ijc.21826.

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Catalytic hydrogenation of eugenol (Mr 164) and isoeugenol (Mr 164) by using synthetic catalyst Ni/-Al2O3 had been carried out. Eugenol transformation into 2-methoxy-4-propylphenol (Mr 166) as a main product could be achieved in 100% and no conversion reaction of eugenol into isoeugenol. If the raw material was 96% trans-isoeugenol or 61% cis-isoeugenol then the product was 67% or 92% of 2-methoxy-4-propylphenol. On the catalytic hydrogenation of trans-isoeugenol into 2-methoxy-4-propylphenol there was no parallel reaction of trans-isoeugenol into cis-isoeugenol. Conversely, catalytic reactio

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2

Cadu, Alban, Kohei Sekine, Jaroslaw Mormul, Dominik M. Ohlmann, Thomas Schaub, and A. Stephen K. Hashmi. "Homogeneous catalysed hydrogenation of HMF." Green Chemistry 20, no. 14 (2018): 3386–93. http://dx.doi.org/10.1039/c8gc01025k.

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Noroozi-Shad, Nazanin, Mostafa Gholizadeh, Mohammad Izadyar, and Hossein Eshghi. "Theoretical Evaluation of the Efficiency of Novel Frustrated Lewis Pairs in the cis-Hydrogenation Reaction of Dimethylacetylene." Progress in Reaction Kinetics and Mechanism 42, no. 4 (2017): 372–83. http://dx.doi.org/10.3184/146867817x14954764850469.

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Frustrated Lewis pairs (FLPs) are the combination of Lewis acid and base motifs where steric hindrance prevents strong adduct formation. Accordingly, the ability of FLPs in small molecule activation and their capability in hydrogen cleavage led to their use in the hydrogenation of a wide range of unsaturated substrates. Here, we investigated theoretically the ability of three intramolecular phosphorus/boron FLPs as bifunctional catalysts in the metal-free hydrogenation of dimethylacetylene to cis-alkene. The mechanism of this hydrogenation reaction, based on the boron acceptor [including –OR s

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Pei, Yuchen, Minda Chen, Xiaoliang Zhong, et al. "Pairwise semi-hydrogenation of alkyne to cis-alkene on platinum-tin intermetallic compounds." Nanoscale 12, no. 15 (2020): 8519–24. http://dx.doi.org/10.1039/d0nr00920b.

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Hu, Shunyou, Linlin Wang, Xiaopeng Chen, Xiaojie Wei, Zhangfa Tong та Lijiang Yin. "The conversion of α-pinene to cis-pinane using a nickel catalyst supported on a discarded fluid catalytic cracking catalyst with an ionic liquid layer". RSC Advances 9, № 11 (2019): 5978–86. http://dx.doi.org/10.1039/c9ra00675c.

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6

Kirkwood, Kathleen, and S. David Jackson. "Hydrogenation and Hydrodeoxygenation of Oxygen-Substituted Aromatics over Rh/silica: Catechol, Resorcinol and Hydroquinone." Catalysts 10, no. 5 (2020): 584. http://dx.doi.org/10.3390/catal10050584.

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The hydrogenation and hydrodeoxygenation (HDO) of dihydroxybenzene isomers, catechol (1,2-dihydroxybenzene), resorcinol (1,3-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene) was studied in the liquid phase over a Rh/silica catalyst at 303–343 K and 3 barg hydrogen pressure. The following order of reactivity, resorcinol > catechol > hydroquinone (meta > ortho > para) was obtained. Kinetic analysis revealed that catechol had a negative order of reaction whereas both hydroquinone and resorcinol gave positive half-order suggesting that catechol is more strongly adsorbed. Activ

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Tippett, LM, and RA Massywestropp. "Reduction of Substituted 1-Methylene-1,2,3,4-tetrahydronaphthalene Derivatives." Australian Journal of Chemistry 46, no. 6 (1993): 945. http://dx.doi.org/10.1071/ch9930945.

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The stereoselectivity of reduction of 4-substituted 1-methylene-1,2,3,4-tetrahydronaphthalenes has been investigated by using catalytic hydrogenation and lithium in ammonia solutions. Serrulatane derivatives underwent highly stereoselective catalytic reduction to yield cis products. Lithium/ammonia reduction was less selective but (3R)-7,8-dimethoxyserrulat-1(20)-en-3-ol showed good selectivity to yield predominantly the cis isomer.

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8

Muchalal, M. "THE STEREOCHEMISTRY EFFECT OF EUGENOL, CIS-ISOEUGENOL AND TRANS-ISOEUGENOL ON THEIR CATALYTIC HIDROGENATION." Indonesian Journal of Chemistry 4, no. 2 (2010): 99–105. http://dx.doi.org/10.22146/ijc.21861.

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The stereochemistry effect of eugenol, cis-isoeugenol and trans-isoeugenol on their catalytic hydrogenation by Ni/g-Al2O3 catalyst was investigated. In this investigation, the catalyst is prepared by impregnation of Nickel into solid of γ-Al2O3 in methanol as a solvent. The calcination process, which is followed by reduction, is performed on Muchalal reactor at 400 oC. After that, the catalytic hydrogenation is carried out under hydrogen gas atmosphere by mixing 10 mL sample and 0.5 g Ni/g-Al2O3 catalyst at 200 oC for 3 hours. The stereochemistry effect of reactants is evaluated by computer mo

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Li, Xiuxiu, Cai You, Yusheng Yang та ін. "Rhodium-catalyzed enantioselective hydrogenation of α-amino acrylonitriles: an efficient approach to synthesizing chiral α-amino nitriles". Chemical Communications 53, № 7 (2017): 1313–16. http://dx.doi.org/10.1039/c6cc09662j.

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An efficient asymmetric hydrogenation of α-amino acrylonitriles has been achieved, affording chiral α-amino nitriles in excellent yields and enantioselectivities regardless of the cis–trans configuration of α-amino acrylonitriles.

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Mao, Cong, Jingwei Zheng, Babasaheb M. Matsagar, et al. "Highly-efficient Ru/Al–SBA-15 catalysts with strong Lewis acid sites for the water-assisted hydrogenation of p-phthalic acid." Catalysis Science & Technology 10, no. 8 (2020): 2443–51. http://dx.doi.org/10.1039/d0cy00047g.

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A Ru/Al–SBA-15 catalyst with excess Lewis acid sites displayed excellent efficiency (100%), high cis-isomer selectivity (84%), and exceptional stability towards hydrogenation of p-phthalic acid in water.

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Dissertations / Theses on the topic "Cis-Hydrogenation"

1

Mc, Geehin Peter Kevin Mark. "Hydrogenation, hydrogenolysis and reductive fission reactions of cis dihydrodiols." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252284.

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Cullen, Bernard. "Selective hydrogenation of a multifunctional compound : 2-butyne-1,4-diol to cis-2-butene-1,4-diol." Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412969.

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Sheldrake, Helen M., and T. W. Wallace. "Reduction of Propargylic Sulfones to (Z)-Allylic Sulfones using Zinc and Ammonium Chloride." 2007. http://hdl.handle.net/10454/3451.

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No<br>Propargylic sulfones can be cis-hydrogenated using commercial zinc powder and ammonium chloride in THF¿water at room temperature, the major products being the corresponding (Z)-allylic sulfones. Other reducible groups (alkene, benzyloxy) are not affected. Allenylsulfones are implicated in one of the possible reaction pathways.

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許振宏. "Catalytic hydrogenation of trans, trans, cis-1, 5, 9-cyclododecatriene over Ni/MCM-41 mesoporous molecular sieves." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/96277131532165785402.

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碩士<br>東海大學<br>化學系<br>91<br>The catalytic reaction between trans, trans, cis- 1, 5, 9- cyclododecatriene and hydrogen gas has been studied using nickel containing mesoporous molecular sieve MCM-41. The catalysts of Ni/Si-MCM-41 and Ni/Al-MCM-41 were characterized with various techniques of XRD, TEM, gas sorption analyzer, NH3-TPD, H2-TPR, solid state NMR, CO-chemisorption and FT-IR to obtain the catalyst properties, viz. the structure, the surface area, the acidity, the reducibility and the metal dispersion. Increasing the SiO2/Al2O3 mol ratio enhances the structural order and the surface area

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Book chapters on the topic "Cis-Hydrogenation"

1

Ilinitch, O. M., P. A. Simonov, and F. P. Cuperus. "Nanosize Palladium Loaded Catalytic Membrane: Preparation and Cis-Trans Selectivity in Hydrogenation of Sunflower Oil." In Preparation of Catalysts VII, Proceedings of the 7th International Symposium on Scientific Bases for the Preparation of Heterogeneous Catalysts. Elsevier, 1998. http://dx.doi.org/10.1016/s0167-2991(98)80167-5.

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2

Guo, Xiangyao, and G. L. Rempel. "Hydrogenation of Cis-1,4-Polybutadiene and Nitrile-Butadiene Copolymers Using Rucl(co)(ocoph)(Pph3)2 as Catalyst." In Progress in Catalysis, Proceedings of the 12th Canadian Symposium on Catalysis. Elsevier, 1992. http://dx.doi.org/10.1016/s0167-2991(08)60806-x.

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3

Taber, Douglass F. "The Theodorakis Synthesis of (–)-Jiadifenolide." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0085.

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There has recently been a great deal of interest in the synthesis of natural products that promote neurite outgrowth. Emmanuel A. Theodorakis of the University of California, San Diego described (Angew. Chem. Int. Ed. 2011, 50, 3672) the preparation of one of the most potent (10 nM) of these, (–)-jiadifenolide 3. Fittingly, a key transformation en route to this highly oxygenated seco-prezizaane was the oxidative rearrangement of 1 to 2. The starting point for the synthesis was the commercially available diketone 4. Allylation followed by addition to 5 gave the prochiral triketone 6. Enantioselective aldol condensation following the Tu/Zhang protocol then delivered the bicyclic enone 7. Alkylation to give 8 proceeded with high diastereoselectivity, perhaps controlled by the steric bulk of the silyloxy group. Exposure of the protected ketone to the McMurry reagent PhNTf2 gave the enol triflate 9, which smoothly carbonylated to the lactone 10. Epoxidation with alkaline hydrogen peroxide followed by oxidation gave the carboxylic acid, which spontaneously opened the epoxide, leading to the bis lactone 1. With 1 in hand, the stage was set for the key oxidative rearrangement to 2. It was envisioned that epoxidation would generate the cis-fused 11, which on oxidation would undergo acid-catalyzed elimination to give 12. The newly freed OH would then be in position to engage the lactone carbonyl, leading to 2. In the event, oxidation of the epoxide with the Dess-Martin reagent required sonication for 2 h. The rearranged lactone, even though it was susceptible to further oxidation, was secured in 38% overall yield from 1. After hydrogenation and protection, preparation of the enol triflate 13 from the congested cyclopentanone necessitated the use of the more reactive Comins reagent. Hydrogenation of the trisubstituted alkene from coupling with Me3Al then required 90 atmospheres of H2 overpressure. Hydroxylation of the lactone 14 with the Davis oxaziridine followed by further oxidation to the ketone with the Jones reagent and deprotection then completed the synthesis of (–)-jiadifenolide 3.

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4

Winterbottom, J. M., H. Marwan, J. Viladevall, S. Sharma, and S. Raymahasay. "Selective catalytic hydrogenation of 2-butyne-1,4-diol to cis-2-butene-1,4-diol in mass transfer efficient slurry reactors." In Studies in Surface Science and Catalysis. Elsevier, 1997. http://dx.doi.org/10.1016/s0167-2991(97)80888-9.

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5

Taber, Douglass F. "Reactions of Alkenes." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0028.

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Ana C. Fernandes of the Instituto Superior Técnico, Lisboa, devised (Tetrahedron Lett. 2010, 51, 1048) an effective Re catalyst for the solvent-free hydrogenation of an alkene 1. Yasushi Imada and Takeshi Naota of Osaka University showed (Organic Lett. 2010, 12, 32) that a flavin could catalyze the hydrogenation of an alkene 3. Note that the thioether was stable under these conditions. Huanfeng Jian of the South China University of Technology developed (J. Org. Chem. 2010, 75, 2321) a Pd-based protocol for the oxidative cleavage of an alkene 5. The cleavage could be halted at the cis diol. K. C. Nicolaou of Scripps/La Jolla optimized (Organic Lett. 2010, 12, 1552) a complemetary cleavage of an alkene 7, again proceeding via the diol. J. R. Falck of UT Southwestern established (J. Org. Chem. 2010, 75, 1701) the Heck-type oxidative silylation of an alkene 9 to the Z -silane 10. Timothy F. Jamison of MIT effected (Chem. Commun. 2010, 46, 907) the borylation of an alkene 11. Kálmán Szabó of Stockholm University reported (Angew. Chem. Int. Ed. 2010, 49, 4051) a complementary approach for effecting the same transformation. Cathleen M. Crudden of Queen’s University, Kingston, observed (J. Am. Chem. Soc. 2010, 132, 131) that Rh-catalyzed hydroboration of 13 delivered the borane 14. Tehshik P. Yoon of the University of Wisconsin used (J. Am. Chem. Soc. 2010, 132, 4570) Fe to catalyze the addition of an oxaziridine 16 to an alkene 15. Yasuhiro Shiraishi of Osaka University improved (J. Org. Chem. 2010, 75, 1450) the photochemical addition of acetone to an alkene 18. Chul-Ho Jun of Yonsei University described (Tetrahedron Lett. 2010, 51, 160) a related procedure. Professor Jamison effected (J. Am. Chem. Soc. 2010, 132, 6880) the branching homologation of an alkene to give 21 . F. Dean Toste of the University of California, Berkeley, accomplished (J. Am. Chem. Soc. 2010, 132, 8885) the oxidative homologation of an alkene to the ester 22. Markus R. Heinrich of the Universität Erlangen-Nürnberg developed (Tetrahedron Lett. 2010, 51, 1758) the tandem addition of the hydroperoxide 23 and a diazonium salt 24, leading to 25.

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6

Taber, Douglass. "Stereocontrolled Carbocyclic Construction: (-)-Mintlactone (Bates), (-)-Gleenol (Kobayashi), (-)-Vibralactone C (Snider)." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0081.

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Nigel S. Simpkins, now at the University of Birmingham, found (Chem. Commun. 2008, 5390) that the prochiral cyclopropane amide 1 could be deprotonated to give, after alkylation, the substituted cyclopropane 3 with high enanantio- and diastereocontrol. In the course of a synthesis of (+)-Lineatin, Ramon Alibés of the Universitat Autònoma de Barcelona optimized (J. Org. Chem. 2008, 73, 5944) the photochemical cycloaddition of 4 and 5 to give, after reductive dechlorination, the cyclobutene 6. In a related reaction, José L. García Ruano and M. Rosario Martín of the Universidad Autónoma de Madrid observed (J. Org. Chem. 2008, 73, 9366) that the cycloaddition of 8 to 7 proceeded with high regio- and diastereocontrol, to give the cyclopentene 9. Joseph M. Ready of UT Southwestern in Dallas developed (Angew. Chem. Int. Ed. 2008, 47, 7068) a powerful new cyclopentannulation, condensing the cyclopropane derived from the addition of 11 to 10 with the protected ynolate 12 to give 13, in the presence of a modified Lewis acid catalyst. Chun-Chen Liao of the National Tsing Hua University, Hsinchu described (Angew. Chem. Int. Ed. 2008, 47, 7325) the oxidative ring contraction of the o-alkoxy phenol 14 to the cyclopentenone 15. Stéphane Quideau of the Université de Bordeaux reported (Organic Lett. 2008, 10, 5211) a related ring contraction. We uncovered (J. Org. Chem. 2008, 73, 9479) a simple protocol for the in situ conversion of an ω-alkenyl ketone such as 16 to the corresponding diazo compound, leading, via dipolar cycloaddition, to the adduct 17. Ulrich Zutter of Roche Basel described (J. Org. Chem. 2008 , 73, 4895), in a synthesis of Tamiflu, the hydrogenation of 19 to give the cyclohexane with all-cis diastereocontrol. Selective removal of the methyl ethers with trimethylsilyl iodide set the stage for enzymatic ester hydrolysis, delivering 20 in high ee.

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Taber, Douglass F. "The Li/Yang Synthesis of (±)-Maoecrystal V." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0100.

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Maoecrystal V 3, isolated from the Chinese medicinal herb Isodon eriocalyx, shows selective inhibition of HeLa cells at low nanomolar concentration (IC50 = 60 nm). Chuang-Chuang Li of Shenzen Graduate School of Peking University and Zhen Yang of Peking University, Beijing, designed (J. Am. Chem. Soc. 2010, 132, 16745) the first total synthesis of 3, based on the intramolecular Diels-Alder cyclization of 1 to 2. The preparation of 1 began with the ketone 4. Methoxycarbonylation of 4 followed by with high diastereocontrol to coupling with 6 delivered 7. As expected, hydride reduction of the cyclic β-keto ester proceeded give the undesired trans diastereomer. Fortunately, the bulky tetrabuylammonium borohydride delivered the cis diastereomer, which could be reduced to the diol 8. Rh-catalyzed carbene insertion into the O-H bond followed by condensation with formaldehyde then completed the preparation of the precursor 10. Deprotection of 10 followed by oxidation presumably gave 1. There are two faces to the diene of 1, and then the acetoxylated stereogenic center, so four products are possible. In the event, three of the four were observed, of which 2 was the major. To complete the synthesis of 3, the secondary alcohol of 11 was introduced by allylic bromination followed by radical reduction and trapping with TEMPO. The acetoxy group was reduced off, and then the more reactive alkene was removed by selective hydrogenation. Oxidation and base treatment then delivered the equilibrium mixture of (±)-maoecrystal V 3 and its methyl epimer. The synthesis of 3 as reported led to the racemate of the natural product. The starting cyclohexene 1 can be prepared (Tetrahedron Lett . 2000, 41, 3871) from 2,2-dimethylcyclohexane- 1,3-dione 12. Yeast reduction of the prochiral 12 is known to proceed with high (S)-induction. It may be that a route could be devised from the reduction product 13 to enantiomerically pure 7.

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8

Taber, Douglass F. "Alkaloid Synthesis: ( S )-Nicotine (Helmchen), (+)-CP-99,994 (Shi),(-)-Adaline (Yu), (-)-Securinine (Bayó n/Figueredo), Alkaloid 223A (Aubé ), (-)-Huperzine A (Fukuyama) 110." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0057.

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The recent development of practical methods for the asymmetric preparation of amines has enabled creative approaches to alkaloid construction. Günter Helmchen of the Ruprecht-Karls-Universit ät Heidelberg developed (Synlett 2009, 1413) an iridium catalyst that mediated the enantioselective amination of the allylic carbonate 1 to give 2. Hydroformylation followed by reduction then completed the synthesis of ( S )-nicotine 3. Yian Shi of Colorado State University devised (J. Org. Chem. 2009, 74, 7577) a Pd catalyst for the enantioselective oxidative diamination of terminal alkenes such as 4. The product 6 was readily carried on to (+)-CP-99,994, a potent and selective nonpeptide substance P receptor antagonist. Chan-Mo Yu of Sungkyunkwan University prepared (Synlett 2009, 1498) the alcohol corresponding to the azide 8 by BINOL-catalyzed addition of an allyl stannane to the corresponding aldehyde. Reduction of the azide and subsequent intramolecular condensation with the ketone gave an imine, which was cyclized with Bu3SnF to 9. Oxidative cleavage then delivered (-)-adaline 10. Barry M. Trost of Stanford University developed a family of Pd catalysts for the enantioselective coupling of racemic butadiene monoepoxide 12 with a range of nucleophiles. Pau Bayón and Marta Figueredo of the Universitat Autónoma de Barcelona extended (J. Org. Chem. 2009, 74, 6199) that range to include glutarimide 11 and succinimide. The adduct 13 provided the enantiomerically pure core for a total synthesis of (-)-securinine 14, and others of the Securinega alkaloids. Jeffrey Aubé of the University of Kansas prepared (Organic Lett. 2009, 11, 4140) the enantiomerically enriched ketone 15 by the enantioselective hydroboration of norbornadiene, followed by oxidation and alkylation. Intramolecular Schmidt cyclization following the protocol he had developed converted 15 into 16. He then took advantage of the still substantial ring strain of the expanded norbornene to drive ring-opening metathesis, giving, after hydrogenation, the lactam 17. He was able to selectively convert 17 into either 18 or the diastereomer in which the ethyl groups are cis one to another by varying the acid used in the final reductive work-up.

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9

Taber, Douglass F. "The Thomson Synthesis of (–)-GB17." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0096.

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(–)-GB17 3 is one of the Galbulimima alkaloids, a family that shows a wide range of interesting physiological activity. Regan J. Thomson of Northwestern University devised (Angew. Chem. Int. Ed. 2012, 51, 2481) a convergent assembly of 3, a key step of which was the intramolecular Michael cyclization of 1 to 2. The hydroxy aldehyde 6 was prepared by alkylation of the dithiane 4 with 5, followed by hydrolysis. The preparation of 9, by condensation of 8 with 7 followed by hydrogenation and protection, had been reported by Lhommet. Condensation of 9 with the linchpin reagent 10 gave an intermediate keto phosphonate, which was combined with 6 to give, after oxidation, the aldehyde 1. Two new stereogenic centers are created in the course of the cyclization of 1. The authors found that the TFA salt 11 of the Hayashi catalyst delivered 2 with high diastereocontrol. Control experiments showed that the buttressing effect of the dithiane was required for the cyclization. The authors then explored the next intramolecular Michael cyclization of 13 to 14. In this cyclization, the stereogenic center at 6 is in jeopardy by elimination and readdition. Cyclization of the trans unsaturated ester led to the wrong diastereomer of 14, but cyclization of the cis ester 13, prepared by the Still-Gennari protocol, cleanly gave the desired diastereomer. The reaction worked best with the free amine. Under the conditions of the reaction the Michael addition product spontaneously cyclized to the lactam 14. The ketone of 14 was selectively enolized, then converted to its enol triflate, which under Pd-mediated reduction gave the alkene 15. Alkylation of 15 with 16 predominantly gave the diene 18. Hydrolysis of the dithiane to the ketone followed by reduction gave mainly the desired equatorial alcohol, which was cleaved oxidatively to (–)-GB17 3. Although there have been many isolated reports of the utility of intramolecular Michael addition as a synthetic method, there has been little systematic investigation. The optimization studies that are the heart of this work are a welcome addition.

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10

Taber, Douglass F. "C–N Ring Construction: The Weinreb Synthesis of Myrioneurinol." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0055.

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Terminal epoxides such as 1 are readily available in high enantiomeric excess. Christopher D. Bray of Queen Mary University of London observed (Tetrahedron Lett. 2014, 55, 5890) clean inversion in the conversion of 1 to the aziridine 3 with the reagent 2. Yong-Chun Luo and Peng-Fei Xu of Lanzhou University opened (Org. Lett. 2014, 16, 4896) the activated cyclopropane 4 with benzyl azide, then heated the adduct to expel N2, leading to the azetidine 5. Zhenming Du of Roche Shanghai and Michelangelo Scalone of Roche Basel developed (Org. Process Res. Dev. 2014, 18, 1702) practical conditions for the asymmetric hydrogenation of 6 to the pyrrolidine 7. Young Ho Rhee of the Pohang University of Science and Technology showed (Chem. Eur. J. 2014, 20, 16391) that depending on the diol protecting group, addition of allyl silane to 8 could lead to either the cis product 9 or the trans diastereomer (not illustrated). Ohyun Kwon of UCLA used (J. Am. Chem. Soc. 2014, 136, 11890) an organocatalyst to add the racemic allene 10 to 11 to give 12 in high ee. Tom Livinghouse of Montana State University cyclized (Angew. Chem. Int. Ed. 2014, 53, 14352) the hydrazine 13 into an intermediate organozinc species that was then coupled with allyl bromide to give 14. Yonggang Chen of Merck Process and Xumu Zhang of Rutgers University devised (Angew. Chem. Int. Ed. 2014, 53, 12761) practical conditions for the reduction of 15 to the piperidine 16. Teck-Peng Loh of the Nanyang Technological University and the University of Science and Technology of China effected (Chem. Commun. 2014, 50, 8324) asymmetric phenylation of biomass-derived 17 to give an intermediate that was oxidatively rearranged, then reduced to 18. Robert R. Knowles of Princeton University showed (J. Am. Chem. Soc. 2014, 136, 12217) that the cyclization of 19 to 20 proceeded with high diastereoselectivity. Maria J. Alves of the Universidade do Minho osmylated (Synlett 2014, 25, 1751) the adduct from the Diels–Alder cycloaddition of 22 to 21 to give 23 in high ee.

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