Study of the Reaction of Bulky Aryllithium Reagents with 3,4-Dimethyl-2,5-diphenyl-1,3,2-oxazaphospholidine-2-borane Derived from Ephedrine
作者:Michel (Massoud S.) Stephan、Damjan Šterk、Barbara Modec、Barbara Mohar
DOI:10.1021/jo7014505
日期:2007.10.1
by others. In fact, several 2,6-disubstituted aryl groups were successfully appended to the phosphorus atom, furnishing the corresponding (N-ephedrino)phosphine boranes 2a−g with dr >99:1. However, when the attack on the phosphorus atom is hindered, deprotonation on the benzylic position occurs, leading to the formation of enantiomerically pure trans-(N-methylamino)(phenyl)(1-phenyl-1-propenyloxy)phosphine-P-borane
研究了对映体纯的3,4-二甲基-2,5-二苯基-1,3,2-氧杂氮磷吡啶-2-硼烷(1)与各种笨重的芳基锂试剂的开环。我们的结果与他人获得的结果并不完全一致。实际上,几个2,6-二取代的芳基成功地连接到了磷原子上,从而为dr(99:1 )提供了相应的(N- ephedrino)膦硼烷2a - g。然而,当在磷原子上的攻击受到阻碍,在苄基位置的去质子化发生,从而导致对映异构纯的形成反式- (Ñ甲基氨基)(苯基)(1-苯基-1-丙烯基氧基)膦P -硼烷(3)。虽然2,2'-二锂-1,1'- biarenes引线攻击到相应的(P -苯基)磷杂环衍生物(4I,Ĵ)和[双(Ñ -ephedrino)](苯基)膦P -硼烷(5),1,1'- dilithiometallocenes(M =铁,钌)引线攻击的1,1'-双可分离的非对映体混合物[(ñ -ephedrino)(苯基)膦基P -硼烷]的金属茂(2k,l