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

The use of hyphenated techniques combining flash-vacuum pyrolysis with Four ier transform infrared spectroscopy or tandem mass spectrometry has indicat ed that N-aryl-3,6-dihydro[1,2]dithiolo[4,3-c][1,2]dithiolimines 2a,b and 3 a,b are efficient precursors of a series of new neutral and/or ionized hete rocumulenes in the gas phase. Typical identified cumulenes were N-arylimino butatrienes, ArN=C=C=C=C=X, X = NAr or S (as radical cations), N-aryliminop ropadienethiones, ArN=C=C=C=S, and N-aryliminopropadienethiones S-sulfide ( as radical cations). Furthermore, the gas phase stability of NCCCS and NCCC CS 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.