Enantioselective Preparation of Alcohols and Amines
Renat Kadyrov of Evonik Degussa and Magnus Rueping of RWTH Aachen developed (Angew. Chem. Int. Ed. 2009, 49, 7556. DOI: 10.1002/anie.200902835) an effective catalyst for the enantioselective hydrogenation of an α-hydroxy ketone 1 to the 1,2-diol 2. Yong-Gui Zhou of the Dalian Institute of Chemical Physics showed (J. Org. Chem. 2009, 74, 5633. DOI: 10.1021/jo900790k) that a sultam such as 3 could be reduced with high ee to the sulfonamide 4. They also used this same approach to prepare both α-aryl and α,α-diaryl amines.
David W. C. MacMillan of Princeton University described (Angew. Chem. Int. Ed. 2009, 49, 5121. DOI: 10.1002/anie.200901855) the optimized enantioselective α-chlorination of an aldehyde 5 and the direct processing of the product to the epoxide 6. Erick M. Carreira of ETH Zürich reported (Synlett 2009, 2076. DOI: 10.1055/s-0029-1217562) an alternative route to high ee epoxides by decarbonylation of an epoxy aldehyde 7. James P. Morken of Boston College established (J. Am. Chem. Soc. 2009, 131, 13210. DOI: 10.1021/ja9047762) a procedure for the enantioselective bis borylation of a terminal alkene 9, leading after oxidation to the 1,2-diol 10. Ben L. Feringa of the University of Groningen took advantage (J. Am. Chem. Soc. 2009, 131, 9473. DOI: 10.1021/ja902591g) of their alternative Wacker conditions to convert a primary allylic carbonate 11 to the protected β-amino aldehyde12.
Chao-Shan Da of Lanzhou University devised (Org. Lett. 2009, 11, 5578. DOI: 10.1021/ol9020942) additives that allow the direct enantioselective addition of a Grignard reagent 14 to an aldehyde. The enantioselective addition of substituted ketenes to aldehydes has long been established. Yun-Ming Lin of the University of Toledo developed (Synlett 2009, 1675. DOI: 10.1055/s-0029-1217332) a catalyst system for the enantioselective addition of ketene 17 itself. An alkenyl silane 19 can readily be prepared from the corresponding terminal alkene (J. Org. Chem. 2010, 75, 1701. DOI: 10.1021/jo902678p). Koichi Mikami of the Tokyo Institute of Technology showed (J. Am. Chem. Soc. 2009, 131, 13922. DOI: 10.1021/ja906164p). that such alkenyl silanes add to ethyl glyoxylate 20 with high ee.
Amir H. Hoveyda of Boston College devised (J. Am. Chem. Soc. 2009, 131, 18234. DOI: 10.1021/ja9089928) a procedure for the enantioselective conversion of a terminal alkyne 22 to the 1,2-bis boryl alkane, that he took on directly to the coupled product 24. Note that these are the same sort of 1,2-bis boryl alkanes as those described by Professor Morken in the conversion of 9 to 10.
Luca Bernardi and Alfredo Ricci of the University of Bologna optimized (Angew. Chem. Int. Ed. 2009, 49, 5694. DOI: 10.1002/anie.200900701) a quinidine-based catalyst for the enantioselective addition of the commercial 26 to the aldehyde derivative 25 to give the β-amido ester 27. Géraldine Masson and Jieping Zhu of Gif-sur-Yvette reported (Org. Lett. 2009, 11, 4648. DOI: 10.1021/ol901920s) a related catalyst for the enantioselective aza-Morita-Baylis-Hillman addition of 29 to the imine 28. Eric N. Jacobsen of Harvard University developed (Nature 2009, 461, 968. DOI: 10.1038/nature08484) a practical procedure for the Strecker cyanation of the pivaldehyde imine 31. Andrew D. Smith of the University of St. Andrews designed (Angew. Chem. Int. Ed. 2009, 49, 8914. DOI: 10.1002/anie.200904333) an organocatalyst for the enantioselective rearrangement of 33 to 34.