Substituted acetic acids or acetyl chlorides react with phosphorus oxychloride in DMF to yield the vinamidinium salts 3a-j in moderate to excellent recrystallized yields (28-90%). The cations are conveniently isolated as their hexafluorophosphate salts, which are easily handled nonhygroscopic solids. The nitro compound 31 is prepared in 91% yield by nitration of the parent vinamidinium 3k. The X-ray crystal structure is reported for the 2-phenyl isomer 3e and displays minimal overlap of the two π-systems.
All Science Journal Classification (ASJC) codes
- Organic Chemistry