The successive treatment of beta-(trimethylsilyl)allyl phenyl sulfides with titanocene(II)-1-butene complex and ketones produced tertiary gamma-(trimethylsilyl)homoallylic alcohols with good anti-selectivity, which reacted with a variety of organic halides in the presence of copper(I) tert-butoxide to afford the cross-coupling products, gamma-substituted homoallylic alcohols.
Preparation of methylenedifluorocyclopropanes via cyclopropyl anion promoted β-elimination
Preparation of methylenedifluorocyclopropanes 2 through the beta-elimination reaction promoted by difluorocyclopropyl anion formed by cleavage of C-Si bond with TBAF is described. Base-catalyzed isomerization of 2 to difluorocyclopropene 11 shows the latter structure thermodynamically more stable in contrast to non-fluorinated cases. Application of this method to the synthesis of methylenedifluorocyclopropylglycine (F(2)MCPG) derivative 17 is also presented. (C) 1999 Elsevier Science Ltd. All rights resented.
COREY, E. J.;RITTER, KURT;YUS, MIGUEL;NAJERA, CARMEN, TETRAHEDRON LETT., 28,(1987) N 31, 3547-3550
作者:COREY, E. J.、RITTER, KURT、YUS, MIGUEL、NAJERA, CARMEN