Academic literature on the topic 'MAP aryl amides'

Andrey P. A ntonchick of the Max-Planck-Institut Dortmund devised (Org. Lett. 2012, 14, 5518) a protocol for the direct amination of an arene 1 to give the amide 3. Douglass A. Klumpp of Northern University showed (Tetrahedron Lett. 2012, 53, 4779) that under strong acid conditions, an arene 4 could be carboxylated to give the amide 6. Eiji Tayama of Niigata University coupled (Tetrahedron Lett. 2012, 53, 5159) an arene 7 with the α-diazo ester 8 to give 9. Guy C. Lloyd-Jones and Christopher A. Russell of the University of Bristol activated (Science 2012, 337, 1644) the aryl silane 11 to give an intermediate that coupled with the arene 10 to give 12. Ram A. Vishwakarma and Sandip P. Bharate of the Indian Institute of Integrative Medicine effected (Tetrahedron Lett. 2012, 53, 5958) ipso nitration of an areneboronic acid 13 to give 14. Stephen L. Buchwald of MIT coupled (J. Am. Chem. Soc. 2012, 134, 11132) sodium isocyanate with the aryl chloride 15 (aryl triflates also worked well) to give the isocyanate 16, which could be coupled with phenol to give the carbamate or carried onto the unsymmetrical urea. Zhengwu Shen of the Shanghai University of Traditional Chinese Medicine used (Org. Lett. 2012, 14, 3644) ethyl cyanoacetate 18 as the donor for the conversion of the aryl bromide 17 to the nitrile 19. Kuo Chu Hwang of the National Tsig Hua University showed (Adv. Synth. Catal. 2012, 354, 3421) that under the stimulation of blue LED light the Castro-Stephens coupling of 20 with 21 proceeded efficiently at room temperature. Lutz Ackermann of the Georg-August-Universität Göttingen employed (Org. Lett. 2012, 14, 4210) a Ru catalyst to oxidize the amide 23 to the phenol 24. Both Professor Ackermann (Org. Lett. 2012, 14, 6206) and Guangbin Dong of the University of Texas (Angew. Chem. Int. Ed. 2012, 51, 13075) described related work on the ortho hydroxylation of aryl ketones. George A. Kraus of Iowa State University rearranged (Tetrahedron Lett. 2012, 53, 7072) the aryl benzyl ether 25 to the phenol 26. The synthetic utility of the triazene 27 was demonstrated (Angew. Chem. Int. Ed. 2012, 51, 7242) by Yong Huang of the Shenzen Graduate School of Peking University.

Manfred T. Reetz at the Max-Planck-Institut Mülheim and Philipps-Universität Marburg developed (J. Am. Chem. Soc. 2013, 135, 1665) a mutated Thermoethanolicus brockii alcohol dehydrogenase for the enantioselective reduc­tion of 4-alkylidene cyclohexanone 1. Using a new C₂-symmetic chiral bisphos­phine ligand (Wingphos, 5), Wenjun Tang at the Shanghai Institute of Organic Chemistry reported (Angew. Chem. Int. Ed. 2013, 52, 4235) the rhodium-catalyzed asymmetric hydrogenation of β-aryl enamide 3. Qi-Lin Zhou of Nankai University utilized chiral spirophosphine oxazoline iridium complexes 8a and 8b for the asymmetric hydrogenation of unsaturated piperidine carboxylic acid 6 (Angew. Chem. Int. Ed. 2013, 52, 6072) and 1,1-diarylethylene 9 (Angew. Chem. Int. Ed. 2013, 52, 1556) with excellent selectivities. The iron- catalyzed chemoselective hydrogenation of α,β-unsaturated aldehyde 11 was demonstrated (Angew. Chem. Int. Ed. 2013, 52, 5120) by Matthias Beller at the University of Rostock. Jeffrey S. Johnson at the University of North Carolina at Chapel Hill showed (J. Am. Chem. Soc. 2013, 135, 594) that asymmetric trans­fer hydrogenation of racemic acyl phosphonate 14 yielded β-stereogenic α- hydroxy phosphonate 16, a reversal in diastereoselectivity observed in the case of α-keto ester analogues. Gojko Lalic of the University of Washington developed (Org. Lett. 2013, 15, 1112) a monophasic copper catalyst system for the selective semireduction of terminal alkyne 17. Alois Fürstner and coworkers at Max-Planck-Institut Mülheim reported (Angew. Chem. Int. Ed. 2013, 52, 355) the ruthenium-catalyzed trans- selective hydro­genation of alkyne 19. Macrocyclic alkynes could also be selectively hydrogenated to E- alkenes using this methodology. Bernhard Breit at the University of Freiburg found (Angew. Chem. Int. Ed. 2013, 52, 2231) that a bimetallic Pd/ Re/ graphite catalyst system was highly active for the hydrogenation of tertiary amide 21 to amine 22. Professor Beller also discovered (Chem. Eur. J. 2013, 19, 4437) that a commercially available ruthenium complex allowed for the effective transfer hydrogenation of aromatic nitrile 23 to benzyl amine 24. Notably, no reductive amination side products were observed. Maurice Brookhart at the University of North Carolina at Chapel Hill used (Org. Lett. 2013, 15, 496) tris(pentafluorophenyl)borane as a highly active catalyst for the selective reduction of carboxylic acid 25 to aldehyde 26 with triethylsilane as a hydride source.

Jianbo Wang of Peking University described (Angew. Chem. Int. Ed. 2010, 49, 2028) the Au-promoted bromination of a benzene derivative such as 1 with N-bromosuccinimide. In a one-pot procedure, addition of a Cu catalyst followed by microwave heating delivered the aminated product 2. Jian-Ping Zou of Suzhou University and Wei Zhang of the University of Massachusetts, Boston, observed (Tetrahedron Lett. 2010, 51, 2639) that the phosphonylation of an arene 3 proceeded with substantial ortho selectivity. Yonghong Gu of the University of Science and Technology, Hefei, showed (Tetrahedron Lett. 2010, 51, 192) that an arylpropanoic acid 6 could be ortho hydroxylated with PIFA to give 7. Louis Fensterbank, Max Malacria, and Emmanuel Lacôte of UMPC Paris found (Angew. Chem. Int. Ed. 2010, 49, 2178) that a benzoic acid could be ortho aminated by way of the cyano amide 8. Daniel J. Weix of the University of Rochester developed (J. Am. Chem. Soc. 2010, 132, 920) a protocol for coupling an aryl iodide 10 with an alkyl iodide 11 to give 12. Professor Wang devised (Angew. Chem. Int. Ed. 2010, 49, 1139) a mechanistically intriguing alkyl carbonylation of an iodobenzene 10. This is presumably proceeding by way of the intermediate diazo alkane. Usually, benzonitriles are prepared by cyanation of the halo aromatic. Hideo Togo of Chiba University established (Synlett 2010, 1067) a protocol for the direct electrophilic cyanation of an electron-rich aromatic 15. Thomas E. Cole of San Diego State University observed (Tetrahedron Lett. 2010, 51, 3033) that an alkyl dimethyl borane, readily prepared by hydroboration of the alkene with BCl3 and Et3 SiH, reacted with benzoquinone 17 to give 18. Presumably this transformation could also be applied to substituted benzoquinones. When a highly substituted benzene derivative is needed, it is sometimes more economical to construct the aromatic ring. Joseph P. A. Harrity of the University of Sheffield and Gerhard Hilt of Philipps-Universität Marburg showed (J. Org. Chem. 2010, 75, 3893) that the Co-catalyzed Diels-Alder cyloaddition of alkynyl borinate 21 with a diene 20 proceeded with high regiocontrol, to give, after oxidation, the aryl borinate 22.

Although natural amino acids are readily available, there is a continuing need for unnatural amino acids. Jon C. Antilla of the University of South Florida has described (J. Am. Chem. Soc. 2007, 129, 5830) a promising approach, based on the enantioselective organocatalytic reduction of imines such as 1 derived from α-keto esters. The aryl group is easily removed to give the primary amine. Mukund P. Sibi of North Dakota State University has developed (J. Am. Chem. Soc. 2007, 129, 4522) an enantioselective Mg catalyst that mediated the addition of benzyl hydrazine 6 to imides such as 5. The initial adduct cyclized to the pyrazolidinone 7. Karl Anker Jørgensen of Aarhus University has reported (Angew. Chem. Int. Ed. 2007, 46, 1983) a complementary protocol for the enantioselective conjugate addition of a nitrogen nucleophile. Enantioselective homologation can also be a powerful approach. Benjamin List of the Max-Planck-Institute, Mülheim has found (Angew. Chem. Int. Ed. 2007, 46, 612; Organic Lett. 2007, 9, 1149) that three-component coupling of acetyl cyanide, an aldehyde and benzylamine under the influence of the Jacobsen thiourea catalyst 10 delivered the onecarbon homologated nitrile 12 in high ee. Other homologation methods are also effective. Li Deng of Brandeis University has shown (Organic Lett. 2007, 9, 603) that under the influence of cinchona-derived quaternary salts, malonates will add to racemic amido sulfones such as 13 to give the β-amino malonate 14 in high ee. Fujie Tanaka and Carlos F. Barbas III of Scripps/La Jolla have found (Angew. Chem. Int. Ed. 2007, 46, 1878) that the simple organocatalyst proline will mediate the aza-Baylis Hillman addition of an unsaturated aldehyde such as 15 to 16 in high ee. The alkene 17 is the kinetic product. On prolonged exposure to the reaction conditions, 17 was equilibrated to the more stable 18 . Ming-Hua Xu and Guo-Qiang Lin of the Shanghai Institute of Organic Chemistry have established (J. Am. Chem. Soc. 2007, 129, 5336) a robust protocol for the enantioselective assembly of -arylated benzylamines such as 21.

Several remarkable one-carbon homologations have recently appeared. André B. Charette of the Université de Montréal reported (J. Org. Chem. 2008, 73, 8097) the alkylation of diiodomethane with alkyl iodides such as 1, to give the diiodoalkane 2. Carlo Punta and the late Ombretta Porta of the Politecnico di Milano effected (Organic Lett. 2008, 10, 5063) reductive condensation of an amine 3 with an aldehyde 4 in the presence of methanol, to give the amino alcohol 5. Timothy S. Snowden of the University of Alabama showed (Organic Lett. 2008, 10, 3853) that NaBH4 reduced the carbinol 7, easily prepared from the aldehyde 6, to the acid 8. Ram N. Ram of the Indian Institute of Technology, Delhi found (J. Org. Chem. 2008, 73, 5633) that CuCl reduced 7 to the chloro ketone 9. Kálmán J. Szabó of Stockholm University extended (Chem. Commun. 2008, 3420) his elegant work on in situ borinate formation, coupling, in one pot, the allylic alcohol 10 with the acetal 11 (hydrolysed in situ) to deliver the alcohol 12 as a single diastereomer. Samir Z. Zard of the Ecole Polytechnique developed (J. Am. Chem. Soc. 2008, 130, 8898) the 6-fluoropyridyloxy ether of 13 as an effective radical leaving group, enabling efficient coupling with 14, activated by dilauroyl peroxide, to give 15. Shu Kobayashi of the University of Tokyo established (Chem. Commun. 2008, 6354) that the anion of the sulfonyl imidate 17 participated in direct Pd-mediated allylic coupling with the carbonate 16. The product sulfonyl imidate 18 is itself of medicinal interest. It is also easily converted to other functional groups, including the aldehyde 19. Jianliang Xiao of the University of Liverpool found (J. Am. Chem. Soc. 2008, 130, 10510) that Pd-mediated coupling of an aldehyde 21 in the presence of pyrrolidine led to the ketone 22. The reaction is probably proceeding via Heck coupling of the aryl halide with the in situ generated enamine. Alois Fürstner of the Max Planck Institut, Mülheim observed (J. Am. Chem. Soc. 2008, 130, 8773) that in the presence of the simple catalyst Fe(acac)3 a Grignard reagent 24 coupled smoothly with an aryl halide 23 to give 25.

John F. Hartwig of the University of California, Berkeley showed (Nature 2012, 483, 70) that intramolecular C–H silylation of 1 selectively gave, after oxidation and acetylation, the bis acetate 2. Gong Chen of Pennsylvania State University coupled (J. Am. Chem. Soc. 2012, 134, 7313) 3 with 4 to give the ether 5. M. Christina White of the University of Illinois effected (J. Am. Chem. Soc. 2012, 134, 9721) selective oxidation of the taxane derivative 6 to the lactone 7. Most of the work on C–H functionalization has focused on the formation of C–C, C–O, and C–N bonds. Donald A. Watson of the University of Delaware developed (Angew. Chem. Int. Ed. 2012, 51, 3663) conditions for the complementary conversion of an alkene 8 to the allyl silane 9, a powerful and versatile nucleophile. Kilian Muniz of ICIQ Tarragona oxidized (J. Am. Chem. Soc. 2012, 134, 7242) the enyne 10 selectively to the amine 11. Phil S. Baran of Scripps/La Jolla devised (J. Am. Chem. Soc. 2012, 134, 2547) a protocol for the OH-directed amination of 12 to 13. Professor White developed (J. Am. Chem. Soc. 2012, 134, 2036) a related OH-directed amination of 14 to 15 that proceeded with retention of absolute configuration. Tom G. Driver of the University of Illinois, Chicago showed (J. Am. Chem. Soc. 2012, 134, 7262) that the aryl azide 16 could be cyclized directly to the amine, which was protected to give 17. As illustrated by the conversion of 18 to 20 devised (Adv. Synth. Catal. 2012, 354, 701) by Martin Klussmann of the Max-Planck-Institut, Mülheim, C–H functionalization can be accomplished by hydride abstraction followed by coupling of the resulting carbocation with a nucleophile. Olafs Daugulis of the University of Houston used (Angew. Chem. Int. Ed. 2012, 51, 5188) a Pd catalyst to couple 21 with 22 to give 23 with high diastereocontrol. Yoshiji Takemoto of Kyoto University cyclized (Angew. Chem. Int. Ed. 2012, 51, 2763) the chloroformate 24 directly to the oxindole 25.