在存在CuCN的情况下,通过用锆茂茂-丁烯配合物处理原丙烯酸三乙酯与烯丙基和炔丙基磷酸酯在高S N 2'中在4的α位进行原位生成的γ,γ-二烷氧基烯丙基锆物种4的反应。选择性地分别得到相应的5-链烯酸酯和4,5-链二烯酸酯。在当前的Cu(I)介导的偶联反应中,γ,γ-二烷氧基烯丙基锆物种4用作丙酸酯的合成有用的均烯酸酯阴离子当量。
An efficient method for the direct allylation of alkylhalides catalyzed by simple cobalt(II) bromide has been developed. This reaction, using a variety of substituted allylicacetates or carbonates, provides the linear product as the major product. It displays broad substrate scope and good functional group tolerance.
In the presence of CuCN, reaction of gamma,gamma -dialkoxyallylic zirconium species 1 with acyl chloride or allylic phosphates proceeded at the a-position of 1 to give alkanoates 3 after aqueous work-up. The ketene dialkylacetal moiety in the coupling products 2 can be used for further bond forming reaction with electrophiles such as nitrosobenzene, nitrostyrene or trichloroacetylisocyanate. (C) 2000 Elsevier Science Ltd. Ail rights reserved.
OCHIAI, H.;TAMARU, Y.;TSUBAKI, K., J. ORG. CHEM., 52,(1987) N 19, 4418-4420