benzene or carbontetrachloridesolution. When R cis- or trans-2-butenyl(crotyl), 2-propynyl or 1,2-propadienyl (allenyl), the rearranged α-methallyl, allenyl or 2-propynyl thiocyanates, respectively, are produced. The reactions are quantitative as judged by direct PMR observations. When R possesses only moderate reactivity towards electrophiles, e.g., CH3 as in (CH3)4Sn, polymerisation of (SCN)2