Desymmetrization of prochiral phosphanes using derivatives of (-)-cytisine

作者：Johansson MJ; Schwartz LO; Amedjkouh M; Kann NC^*

来源：European Journal of Organic Chemistry, 2004, 2004(9): 1894-1896.

DOI：10.1002/ejoc.200400006

• asymmetric synthesis
• phosphanes
• enantioselectivity
• sparteine
• lithiation

yHistorically, (-)-sparteine-sec-BuLi has been used to desym-metrize prochiral phosphanes. In this report, derivatives of an alkaloid extracted from the seeds of Laburnum anagyro-ides have been utilized to mimic (+)-sparteine, which is not readily available. In several cases, the enantioselectivities achieved with the (+)-Sparteine surrogates outperformed (-)-sparteine itself in the deprotonation of alkyl-substituted (as well as aryl-substituted) prochiral phosphane derivatives. In addition, use of these surrogates allows a new methodology for a chiral switch in phosphorus chemistry.

• 出版日期2004-4-26