Syntheses of 4-Dialkylamino-5,6-dihydrothiopyrane-2-thiones

Article abstract of DOI:10.1007/BF00909675

4-Dialkylamino-5,6-dihydrothiopyrane-2-thiones 3, 9, 10 are synthesized in good yields by reaction of α,β-unsaturated methylketones with dialkyl-ammonium-dialkyldithiocarbamates 5 or carbon disulfide and secondary amines.The reaction takes place via the corresponding oxobutyl-N,N-dialkyldithiocarbamates 13 and dialkylaminobutenyl-N,N-dialkyldithiocarbamattes 14.Cyclohexenylmethylketone 11 reacts with 5 to give 4-dialkylaminohexahydrothiochromane-2-thiones 12.In dimethylformamide or diethylformamide as solvents aminolysis take place and 4-dimethylamino or 4-diethylaminothiopyrane-2-thiones are also formed.Instead of 3-alken-2-ones 6 also 4-hydroxy-2-alkanones 7 and methylketones 8 (such as acetone), which readily undergo the aldol condensation can be used for the preparation of thiopyrane-2-thiones. - Keywords: Dialkylammonium-dialkyldithiocarbamates, reaction with α,β-unsaturated ketones; Dialkylformamides, aminolysis of; Ketones, α,β-unsaturated, reaction with dialkylammonium-dialkyldithiocarbamates; Thiochroman-2-thiones, -4-dialkylamino, hexahydro-; Thiopyran-2-thiones, 4-dialkylamino-5,6-dihydro-