Cleavage of 2-(1,2,3,4-tetrahydroisoquinolin-1-yl)-2-phenyl-1,3-dithianes with HgO/BF3
摘要:
The title compounds (5) were prepared by addition of 2-phenyl-1,3-dithiane anion (2-lithiated 10) to adequately substituted N-alkyl-3,4-dihydroisoquinolinium salts (7a-7g). Cleavage of compounds 5 with HgO/BF3 affords S-benzoyl-1,3-propanedithiol (4a) and the corresponding disulfide 4c, benzaldehyde, and Hg(I) ions. In contrast to the title compounds, 2-(alpha-dialkylaminobenzyl)-2-phenyl-1 ,3-dithianes (6) yield benzil under these conditions.
8-Methoxyisoquinoline derivatives through ortho-selective metalation of 2-(3-methoxyphenyl)ethylamine
摘要:
Butyllithium in diethyl ether smoothly metalates 2-m-anisyl-N-pivaloylethylamine at the aromatic position flanked by the two substituents. Subsequent reaction with N,N-dimethylformamide followed by acid catalyzed cyclization and reduction gives 8-methoxy-1,2,3,4-tetrahydroisoquinoline.