C. Baldoli et al., REACTION OF THE CONJUGATE BASE OF PROPENYLPYRROLIDINOCARBENE CHROMIUMPENTACARBONYL COMPLEX WITH ELECTROPHILES, Tetrahedron letters, 35(34), 1994, pp. 6377-6380
The conjugate base of ntacarbonyl(propenylpyrrolidinocarbene)chromium(
0) is easily generated at -78 degrees C with LDA and reacts with elect
rophilic reagents to provide the corresponding addition products in sa
tisfactory to good yields. The alpha/gamma regioselectivity depends on
the nature of electrophile and is also discussed in comparison with t
he behavior of the anions of crotonamides