Nucleophilic addition reactions to the ethylnitrilium derivative of nido-carborane 10-EtC N-7,8-C2B9H11

Alkylnitrilium derivatives of nido-carborane 10-RC N-7,8-C2B9H11 (R = Me, Et) have been prepared by the reaction of the parent anion [7,8-C2B9H12](-) with mercury(II) chloride in mixtures of the corresponding nitriles and benzene. Hydrolysis of 10-EtC N-7,8-C2B9H11 resulted in iminol 10-EtC(OH)=QHN-7,8-C2B9H11 which on treatment with a base gave the corresponding amide 10-EtC(QO)=HN-7,8-C2B9H11. The reactions of 10-EtC N-7,8-C2B9H11 with alcohols and thiols were found to give stable imidates and thioimidates 10-EtC(XR)=QHN-7,8-C2B9H11 (X = O, R = Me, Et, iPr, Bu; X = S, R = Et, Bu, Hx) as mixtures of E- and Z-isomers that were successfully separated by column chromatography. The crystal molecular structures of E-10-EtC(OR)=QHN-7,8-C2B9H11 (R = Et, i-Pr, Bu) and Z-10-EtC(SEt)=QHN-7,8-C2B9H11 were determined by single crystal X-ray diffraction.