Propyniminium Salts - Synthesis, , and Cycloadditions
The propyniminium triflates 6 are obtained from 3-trifloxypropeniminium triflates 5 by elimination of triflic acid.Reaction with enaminones yields the 2-alkenyl-vinamidinium salts 14 and 18, resp., which result from ring-opening of intermediate cyclobuten