A new route to N-aryl 2-alkenamides, N-allyl N-aryl 2-alkenamides, and N-aryl alpha,beta-unsaturated gamma-lactams from N-aryl 3-(phenylsulfonyl)propanamides
Ec. Wang et al., A new route to N-aryl 2-alkenamides, N-allyl N-aryl 2-alkenamides, and N-aryl alpha,beta-unsaturated gamma-lactams from N-aryl 3-(phenylsulfonyl)propanamides, J CHIN CHEM, 48(1), 2001, pp. 83-90
A series of N-aryl 2-alkenamides were produced efficiently by treating N-ar
yl 3-(phenylsulfonyl)propanamides with potassium tert-butoxide in THF at 0
degrees C. Without isolation, it was further treated with an additional equ
ivalent of potassium tert-butoxide and allyl bromide to give N-allyl N-aryl
2-alkenamides in one pot in good yields. Followed by a ring-closing metath
esis reaction, these N-allyl N-aryl 2-alkenamides were respectively convert
ed into corresponding N-aryl alpha,beta -unsaturated gamma -lactams in mode
rate yields.