Cyclic ammonium salts of dithiocarbamic acid: stable alternative reagents for the synthesis of S-alkyl carbodithioates from organyl thiocyanates in water

ABSTRACT

Carbodithioate esters are important functional organosulfur compounds widely used in diverse fields such as pharmaceuticals, agrochemicals and material sciences. Common preparative methods include reaction of alkyl halides, carbon disulfide and bases under both metal-free and metal-catalyzed conditions. However, organyl thiocyanates have not been previously explored, possibly because of their conversion to organyl disulfides under basic conditions. Here, we report an efficient and practical method for the preparation of libraries of carbodithioate esters from organyl thiocyanates by reacting with cyclic amine-based dithiocarbamic acid salts in water. The protocol is found to be applicable in general to various thiocyanates such as benzyl/aroyl methyl/cinnamyl and so on. Other notable features include no by-products such as disulfides, metal- and alkali-free, aqueous conditions, and finally easy and near-quantitative formation of cyclic amine-based dithiocarbamic acid salt as a stable alternative reagent.

GRAPHICAL ABSTRACT

KEYWORDS:

• Alkyl thiocyanate
• aqueous medium
• carbodithioate ester
• cyclic sec. amine
• dithiocarbamate salt

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

KB and SG thank the UGC, New Delhi, for award of their fellowships under UGC-FDP program.