Aryl radical cyclizations of N-(2-halobenzoyl)-cyclic ketene-N,S-acetals

2-Ethylthiazolines react with 2-halobenzoyl chlorides to form N-(2-halobenzoyl)-cyclic ketene-N,S-acetals, which undergo stereo-controlled radical cyclizations to afford (R,S,S)-3-alkyl-10-methyl-2,3,10,10a-tetrahydrothiazolo[3,2-b]isoquinolin-5-one and (R,R,S)-3-alkyl-10-methyl-2,3,10,10a-tetrahydrothiazolo[3,2-b]isoquinolin-5-one.