REACTION OF POLYSTYRYLLITHIUM AND 2-POLYSTYRYL-1,1-DIPHENYLETHYLLITHIUM WITH METHYL ACETATE, METHYL BENZOATE AND THE CORRESPONDING ACYL CHLORIDES

In the course of the reaction of polystyryllithium (PSL) and 2-polysty ryl-1,1-diphenylethyllithium (PSDPEL) with methyl acetate (MA), methyl benzoate (MB) and acetyl (ACl) and benzoyl (BCl) chlorides as couplin g agents (CA), the quantity of the product of combination P2Y, where P t corresponds to double molecular weight (MW) of the initial PS or PSD PE and the CA residue is referred to as Y, strongly depends on the nat ure of CA, and to a lower degree on the CA/PSL (PSDPEL) ratio and the nature of the solvent (benzene or THF). The maximum yield of P,Y from the reaction of MA and PSL did not exceed 80%, and 12% for MA and PSDP EL. It was shown using CD3COOCH3 and 500 MHz NMR that this incomplete conversion is due to a side reaction of PSL or PSDPEL with the D(H) at oms of the methyl group of MA, proceeding simultaneously with the main reaction and yielding PSD(H) or PSDPED(H). Using a special approach, the polymeric ketone corresponding to the first stage of this rection can be obtained; its yield was in the case of PSL and MA higher than 5 0%. For the PSDPEL-MA system, the product of the reaction, based on NM R data, consists of approximately equal portions of the polymeric keto ne and the product resulting from the side reaction, i. e., PSDPE-H. I n the latter case the sterically hindered polymeric ketone did not rea ct with excess PSL or PSDPEL. Products of the reaction of PSL or PSDPE L with MB dit not contain PSH or PSDPEH, respectively.