Synthesis of Tetrahydro-1-benzazocin-2(1H)-ones Using 8-endo-trig Radical Cyclization of 2,2-Bis(phenylthio)-N-[o-(prop-2-enyl)phenyl]acetamides
摘要:
The effects of N-substituents upon the 8-endo-trig radical cyclization of 2,2-bis(phenylthio)-N-[o-(prop-2-enyl)phenyl]acetamides (4) were examined. The N-(p-methoxybenzyl) (4a) and N-tosyl derivatives (4b), when treated with tributyltin hydride in the presence of a small amount of azoisobutyronitrile, gave regioselectively the corresponding 3,4,5,6-tetrahydro-3-phenylthio-1-benzazocin-2(1H)-ones (5a,b) (8-endo cyclization products) in 40 and 47% yields, respectively, while the N-unsubstituted derivative (4c) afforded the reduction products (6c) and (8) as the major products, Some chemical transformation reactions of 5a are also described.
Highly selective electrochemical fluorination of dithioacetal derivatives bearing electron-withdrawing substituents at the position α to the sulfur atom using poly(HF) salts
Functionalized Heterocumulenes: Synthesis and Applications of Phenylthiomethyl, Methylthiomethyl, Bis[phenylthio]methyl Isocyanates and Phenylthio-acetyl and Methylthio-acetyl Isothiocyanates
Treatment of 2-chloro-N-methyl-N-(6-phenylcyclohex-1-en-1-yl)-acetamide (4a) with Bu3SnH in the presence of AIBN gave a 2.5:1 mixture of cis- and trans-fused N-methyl-7-phenyloctahydroindol-2-ones (5a and 5b) (13% combined yield), N-methyl-N-(2-phenylcyclohex-1-en-1-yl)acetamide (6) (19%), N-methyl-N-(6-phenylcyclohex-1-en-1-yl)acetamide (7) (13%), and N-(cyclohex-1-en-1-yl) -N-methyl-2-phenylacetamide (8) (4%). Similar treatment of the 2,2-bis(phenylthio)acetamide (4b) gave a 1:1 mixture of 5a and 5b (61% combined yield) along with 6 (24%) and 7 (trace). Possible mechanisms for the formation of the products (6)-(8) are also discussed.