ENANTIODIVERGENT TANDEM CARBOMETALATION − ZINC HOMOLOGATION – C-C FRAGMENTATION REACTIONS FOR AN EFFICIENT CONSTRUCTION OF ALLYLIC QUATERNARY CARBON STEREOCENTERS

In recent years, construction of carbon-carbon (C-C) bonds, particularly with concomitant control of newly formed asymmetric centers, is of paramount interest for the development of synthetic routes to complex organic molecules.¹ Thus, C-C bond formation reactions through the use of organometallic species are expected to be a major driver for the synthesis of economically important fine chemicals.² In the repertoire of C-C bond formation with organometallic species, organocopper derivatives occupy a significant place due to their high stereo- and chemoselectivity³, which enables them to add smoothly to the multiple bonds even in the presence of other functionalities. Moreover addition of Et₂Zn and CH₂I₂ (Zinc Homologation), to the carbocuprate derivative will allow to incorporate one additional functionalized carbometallic bond which intern may facilitate the formation of acyclic adducts possessing a challenging all-carbon quaternary stereocenters.

As a part of our ongoing interest on the strained molecular system, present work will describe the tandem carbometallation-zinc homologation of functionalized cyclopropenes for the efficient construction of allylic quaternary stereocenter in good yields.

References:

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