Organic Chemistry Portal
Organic Chemistry Highlights

Monday, July 16, 2012
Douglass F. Taber
University of Delaware

Enantioselective Synthesis of Alcohols and Amines: The Fujii/Ohno Synthesis of (+)-Lysergic Acid

Ramón Gómez Arrayás and Juan C. Carretero of the Universidad Autónoma de Madrid effected (Chem. Commun. 2011, 47, 6701. DOI: 10.1039/C1CC11949D) enantioselective conjugate borylation of an unsaturated sulfone 1, leading to the alcohol 2. Robert E. Gawley of the University of Arkansas found (J. Am. Chem. Soc. 2011, 133, 19680. DOI: 10.1021/ja209187a) conditions for enantioselective ketone reduction that were selective enough to distinguish between the ethyl and propyl groups of 3, to give 4.

Vicente Gotor of the Universidad de Oviedo used (Angew. Chem. Int. Ed. 2011, 50, 8387. DOI: 10.1002/anie.201103348) an over-expressed Baeyer-Villiger monoxygenase to prepare 6 by dynamic kinetic resolution of 5. Li Deng of Brandeis University prepared (J. Am. Chem. Soc. 2011, 133, 12458. DOI: 10.1021/ja205674x) 8 in high ee by kinetic enantioselective migration of the alkene of racemic 7.

Bernhard Breit of the Freiburg Institute for Advanced Studies established (J. Am. Chem. Soc. 2011, 133, 20746. DOI: 10.1021/ja210149g) the oxygenated quaternary center of 10 by addition of benzoic acid to the allene 9. Keith R. Fandrick of Boehringer Ingelheim constructed (J. Am. Chem. Soc. 2011, 133, 10332. DOI: 10.1021/ja2028958) the oxygenated quaternary center of 13 by enantioselective addition of the propargylic nucleophile 12 to 11.

Yian Shi of Colorado State University devised (J. Am. Chem. Soc. 2011, 133, 12914. DOI: 10.1021/ja203138q) conditions for the enantioselective transamination of the α-keto ester 14 to the amine 15. Professor Deng added (Adv. Synth. Catal. 2011, 353, 3123. DOI: 10.1002/adsc.201100447) 18 to an enone 17 to give the protected amine 19. Song Ye of the Institute of Chemistry, Beijing effected (J. Am. Chem. Soc. 2011, 133, 15894. DOI: 10.1021/ja206819y) elimination/addition of an unsaturated acid chloride 20 to give the γ-amino acid derivative 22. Frank Glorius of the Universität Münster added (Angew. Chem. Int. Ed. 2011, 50, 1410. DOI: 10.1002/anie.201006548) an aldehyde 23 to 24 to give the amide 25.

Sentaro Okamoto of Kanagawa University designed (J. Org. Chem. 2011, 76, 6678. DOI: 10.1021/jo200984n) an organocatalyst for the enantioselective Steglich rearrangement of 26, creating the aminated quaternary center of 27. Most impressive of all was the report (Org. Lett. 2011, 13, 5460. DOI: 10.1021/ol2021516) by Hélčne Lebel of the Université de Montréal of the direct enantioselective C-H amination of 28 to give 29.

The alcohol 32 is a key intermediate in the synthesis of (+)-Lysergic Acid (33). Nobutaka Fujii and Hiroaki Ohno of Kyoto University prepared (J. Org. Chem. 2011, 76, 5506. DOI: 10.1021/jo2008324) 31 by Shi epoxidation. Although several competing reduction products were observed under alternative conditions, they were able to establish conditions for selective reduction at the activated benzylic position, to give 32.

D. F. Taber, Org. Chem. Highlights 2012, July 16.
URL: https://www.organic-chemistry.org/Highlights/2012/16July.shtm