Products of the reaction of t-butylcyanoketene (TBCK, Moore's ketene)
with 4-nitro-, 4-methoxy-, 4-fluoro- and 4-chlorostyrene are presented
. Based on the analysis of reaction products we propose a stepwise rea
ction mode for the cases of 4-methoxy, 4-fluoro- and 4-chlorostyrene;
4-nitrostyrene reacted in a (2) pi(s) + (2) pi(a) concerted mode.