Stereospecific synthesis of 1-fluoro olefins via (fluorovinyl)stannanes and an unequivocal NMR method for the assignment of fluoro olefin geometry
作者:James R. McCarthy、Edward W. Huber、Tieu-Binh Le、F. Mark Laskovics、Donald P. Matthews
DOI:10.1016/0040-4020(95)00911-q
日期:1996.1
(Z)-Fluorovinyl sulfones (II) form (fluorovinyl)stannanes (III) on treatment with two equivalents of tributyltin hydride and a catalytic amount of AIBN; the free radical catalyzed reaction proceeds with retention of configuration for 2,2-disubstituted fluorovinyl sulfones (IIa and IIb). Conversion of III to 1-fluoro olefins (IV) is a stereospecific reaction and provides a general method to (E) and (Z)
(E)-和(Z)-氟代乙烯基砜(II)在用两当量的氢化三丁基锡和催化量的AIBN处理时形成(氟乙烯基)锡烷(III);自由基催化的反应会继续保留2,2-二取代的氟乙烯基砜(IIa和IIb)的构型。从III到1-氟烯烃(IV)的转化是立体定向反应,并且提供了对(E)和(Z)氟烯烃的通用方法。该方法的效用以氘代氟代烯烃27,核苷32的合成为例34和34,氨基酸43和47。质子观察,首次使用19 F辐照(1 H- 19 F)NOE差异光谱作为明确方法来指定氟乙烯砜,(氟乙烯)锡烷和氟烯烃的烯烃几何形状。