By treatment of a-substituted acetylacetone derivatives with boron trifluoride etherate a series of earlier unknown boron difluoride complexes is obtained. The series includes binuclear complexes containing boron in the chelate fragment connected via sulfur or selenium atom. Gas chromatographic and spectral characteristics of the obtained compounds were investigated. By means of chromato-mass spectrometry their reaction with hydrazine in acidic and alkaline media was studied.
In the presence of carbon tetrabromide, a variety of dithiocarbamates, xanthates, dithioesters, and thioethers were prepared in one pot by reacting the corresponding dithioic acids or thiols with active methylene compounds/indole derivatives under mild conditions. The formation of a sulfenyl bromide intermediate is proposed as the key step, which initiates the C-S bond formation.