The photostimu lated reaction of N-iperidinyl acetamide anion with a series of chloroarenes in liquid ammonia led to the arylation at α- carbon of the amide. However, a mass photoproduct distribution consisting of 1, 2-diphenylethanne (35%), biphenyl (2%), benzene (5%) and N-ipperdinyl benzoacetamide was observable. In the case of chlorobenzene MO calculation indicated that the odd electron of (PhCH~2COPi)^- might be heavily populated in the piperdinyl portion of the redical anion. Predominant β-scission of (PHCH~2COPi)^- followed by dimerization of benzyl radical gave 1, 3-diphenylethane as the major product. Residence of the odd electron of (ArNu)^- at the polycylic aryl moiety resulted in the electron to transfer ground ArX and formation of the nucleophilic substitution product.

Key words: NUCLEOPHILIC SUBSTITUTION, PHOTOREACTION, LIQUID AMMONIA, ACETAMIDE