Tin(II)chloride Mediated Addition Reaction of Bromonitromethane to Aldehydes

As an electrophile, bromonitromethane was used as a versatile reagent in the synthesis of aminothiophenes and their derivatives as well as in the reaction with nucleophiles such as thiolates, sulphides, thiourea, thiocyanate, iodide and phosphorus based species [1]. Bromonitromethane contains only one carbon atom, therefore it is relevant to C-1 chemistry [2]. In chemical synthesis, it has two advantages over other C-1 synthons: (a) the nitro group of the product can be reduced to an amino group; (b) αhydrogen atoms adjacent to the nitro group in the product, being acidic, are consequently useful for further C-C bond formation via deprotonation-alkylation reactions [3]. It was found that bromonitromethane reacts with imines derived from aromatic aldehydes and ring substituted anilines in the presence of tin(II) chloride to give β -nitroamines via an addition reaction (Scheme 1) [4]. The polarity of bromonitromethane is thereby reversed from an electrophile to a nucleophile.