Organic Chemistry Portal
Organic Chemistry Highlights

Monday, January 31, 2011
Douglass F. Taber
University of Delaware

Construction of Alkylated Stereogenic Centers

Andreas Pfaltz of the University of Basel and Keisuke Suzuki of Tokyo Institute of Technology showed (Angew. Chem. Int. Ed. 2010, 49, 881. DOI: 10.1002/anie.200906362) that the iodohydrin of 1 did not interfere with the enantioselective hydrogenation. J. R. Falck of UT Southwestern developed (J. Am. Chem. Soc. 2010, 132, 2524. DOI: 10.1021/ja910582n) a procedure for the coupling of arene boronic acids with a cyano triflate 3, readily available in high ee from the corresponding aldehyde. Anita R. Maguire of University College Cork devised (J. Am. Chem. Soc. 2010, 132, 1184. DOI: 10.1021/ja909713a) a Cu catalyst for the enantioselective C-H insertion cyclization of 5 to 6. Jin-Quan Yu of Scripps/La Jolla established (J. Am. Chem. Soc. 2010, 132, 460. DOI: 10.1021/ja909571z) a complementary enantioselective C-H functionalization protocol, converting the prochiral 7 into 8 in high ee.

Xumu Zhang of Rutgers effected (Angew. Chem. Int. Ed. 2010, 49, 4047. DOI: 10.1002/anie.201000955) enantioselective branching hydroformylation of 9 to give 10. T. V. RajanBabu of Ohio State University established (J. Am. Chem. Soc. 2010, 132, 3295. DOI: 10.1021/ja1004703) the enantioselective hydrovinylation of a diene 11 to the diene 12. Gregory C. Fu extended (J. Am. Chem. Soc. 2010, 132, 1264, DOI: 10.1021/ja909689t, 5010, DOI: 10.1021/ja1017046) Ni-mediated cross-coupling, both with alkenyl and aryl nucleophiles, to the racemic bromoketone 13.

Hyeung-geun Park and Sang-sup Jew of Seoul National University used (Org. Lett. 2010, 12, 2826. DOI: 10.1021/ol100928v) their asymmetric phase transfer protocol to effect the enantioselective alkylation of the amide 15. Kyung Woon Jung of the University of Southern California showed (J. Org. Chem. 2010, 75, 95. DOI: 10.1021/jo901977n) that the oxidative Pd-mediated Heck coupling of arene boronic acids to 17 could be effected in high ee. Nicolai Cramer of ETH Zurich observed (J. Am. Chem. Soc. 2010, 132, 5340. DOI: 10.1021/ja101469t) high enantioinduction in the cleavage of the prochiral cyclobutanol 19.

Alexandre Alexakis of the University of Geneva achieved (Org. Lett. 2010, 12, 1988. DOI: 10.1021/ol100441r) the long-sought goal of efficient enantioselective conjugate addition of a Grignard reagent to an unsaturated aldehyde 21. Professor Alexakis also (Org. Lett. 2010, 12, 2770. DOI: 10.1021/ol100849j) established conditions for enantioselective conjugate addition to a nitrodiene 23. This procedure worked equally well for β-alkynyl nitroalkenes.

Jun-An Ma of Tianjin University used (J. Org. Chem. 2010, 75, 1402. DOI: 10.1021/jo901991v) organocatalysis to effect the conjugate addition of a variety of ketones, including acetone, to the nitrodiene 25. Again, β-alkynyl nitroalkenes worked well. Shu Kobayashi of the University of Tokyo observed (J. Am. Chem. Soc. 2010, 132, 7890. DOI: 10.1021/ja102555a) that the chiral environment around the catalyst was sufficient to control the absolute configuration of protonation after conjugate addition to 27.

D. F. Taber, Org. Chem. Highlights 2011, January 31.