Enantioselective Total Synthesis and Studies into the Configurational Stability of Bismurrayaquinone A

✍ Scribed by Leah C. Konkol; Dr. Fenghai Guo; Dr. Amy A. Sarjeant; Prof. Regan J. Thomson

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 336 KB
• Volume: 123
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/ange.201104726

✦ Synopsis

Scheme 1. Bismurrayaquinone A (1) and key biphenol 2.

Scheme 2. a) PhI(OAc) 2 (1.2 equiv), MeOH, 91 %; b) Me 2 Zn (0.9 equiv), (S,R,R)-phosphoramidite ligand (4.5 mol %), Cu(OTf) 2 (2 mol %), 45-52 %; c) LDA (1.1 equiv); CuCl 2 (1.1 equiv), 63 %; d) BF 3 •OEt 2 (10 equiv), toluene, reflux, 87 %; e) Br 2 (2.0 equiv), 90 %; f) MeI (10 equiv), KOH (3.0 equiv), 84 %; g) aniline (3.0 equiv), Pd(OAc) 2 (8 mol %), [HPtBu 3 ][BF 4 ] (11 mol %), NaOtBu (11 equiv), toluene, reflux, 93 %; h) BBr 3 (20 equiv); SiO 2 /air, 62 %; i) Pd(OAc) 2 (0.5 equiv), Cu(OAc) 2 (5.0 equiv), AcOH, reflux, 33 %. LDA = lithium diisopropylamide, (S,R,R)-phosphoramidite ligand = (S,R,R)-(À)-(3,5-Dioxa-4-phosphacyclohepta[2,1-a:3,4-a']dinaphthalen-4-yl)bis(1-phenylethyl)amine, Tf = trifluoromethanesulfonyl.