Abstract:
Long back in 1959, Latif and co-workers, department of Chemistry, Rajshahi University , Bangladesh in an attempt to prepare dithiobenzoic acid [Ph-(C=S)-SH] from a mixture of benzaldehyde and ethanol in presence of aqueous sodium sulphide ended up with structure (1), 3-benzyl -2,6-diphenyl-2H-thiopyran-5-carboxaldehyde. The structure of (1) was later confirmed by a number of workers who also proposed mechanism for its formation. But none of them could either isolate or gave any evidence in support of the intermediates proposed in the mechanism. Keeping this view in mind , we took this project to justify their mechanism by using some of the intermediates and some more compounds which could be transformed into those intermediates in situ and ended up with compound (1) , compounds analogous to (1) are (7), (10) , and some other products not analogous to (1) are (9), (15), (15a), (16), (17), and (18). The compound (9) and (10) are analogous to the intermediate (5). One of the products (17) was isolated for the first time is an interesting noble compound having sulphur in an eight membered ring (7-cinnamoyl-2,6,8-triphenylthiocane- 4-one) .
