N-Substituted 3,6-dihydro[1,2]dithiolo[4,3-c][1,2]dithiolimines: potential precursors of new neutral or ionized heterocumulenes in the gas phase

Abstract

The use of hyphenated techniques combining flash-vacuum pyrolysis with Fourier transform infrared spectroscopy or tandem mass spectrometry has indicated that N-aryl-3,6-dihydro[1,2]dithiolo[4,3-c][1,2]dithiolimines 2a,b, and 3a,b, are efficient precursors of a series of new neutral and/or ionized heterocumulenes in the gas phase. Typical identified cumulenes were N-aryliminobutatrienes, ArNCCCCX, X = NAr or S (as radical cations), N-aryliminopropadienethiones, ArNCCCS, and N-aryliminopropadienethiones S-sulfide (as radical cations). Furthermore, the gas phase stability of NCCCS and NCCCCS radicals was also indicated by neutralization–reionization experiments. The behaviour of the N-tert-butyliminodithiolodithioles 2a and 3c was found to be significantly different as the chemistry seems to be dictated by the tert-butyl groups.