Premium
Synthesis and conformational analysis of dibenzodithiocin derivatives
Author(s) -
Sohár P.,
Kövesdi I.,
Szabó J.,
Katócs Á.,
Fodor L.,
Szücs E.,
Bernáth G.,
Tamás J.
Publication year - 1989
Publication title -
magnetic resonance in chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0749-1581
DOI - 10.1002/mrc.1260270809
Subject(s) - chemistry , benzonitrile , benzothiazine , stereochemistry , derivative (finance) , nuclear magnetic resonance spectroscopy , mass spectrometry , medicinal chemistry , chromatography , financial economics , economics
Abstract N ‐(3,4‐Dialkoxyphenylthiomethyl)aroylamides (la, b) reacted with phosphoryl chloride to give not only the expected 4 H ‐ and 2 H ‐1,3‐benzothiazine derivatives (4a, b and 5a, b), but also dibenzodithiocins of new (dibenzo[ d , g ][1,3]dithiocins 2a, b) and known (dibenzo[ b , f ][1,5]dithiocins 3a, b) types. The analogous reaction of the 4‐methylaroylamide 8a furnished the 4 H ‐1,3‐benzothiazine 9a, the dibenzo[ b , f ][1,5]dithiocin derivative 10a and benzonitrile. In contrast, 8b (the chloro analogue of 8a) furnished only benzonitrile and bis(4‐chlorophenylmercapto)methane (11). The structures of the new compounds were confirmed by IR, 1 H and 13 C NMR, and (in part) by mass spectrometry. Temperature‐dependent 1 H NMR studies were used for the conformational analysis of 2a and its disulphone 6a; the nature and free enthalpies of activation of the two different conformational motions occurring at higher temperatures were determined.