Hj. Callot et al., A NOVEL PORPHYRIN ISOMER - HEMIPORPHYCENE - FORMATION AND SINGLE-CRYSTAL X-RAY-DIFFRACTION STRUCTURE DETERMINATION OF A HEMIPORPHYCENE NICKEL-COMPLEX, New journal of chemistry, 19(2), 1995, pp. 155-159
Hemiporphycene ([18]porphyrin-(2,1,1,0)), an additional isomer of the
porphyrin ring system, has been obtained by ring contraction of a homo
porphyrin. Two isomeric triphenylcarboethoxyhemiporphycene nickel comp
lexes and a corresponding free base have been characterized and the X-
ray structure analysis of one of the nickel complexes carried out.