M. Ishizaki et al., A facile synthesis of spiro-cyclopentenones from various 1-alkynes and cyclic exo-methylene compounds by intermolecular Pauson-Khand reaction, HETEROCYCLE, 55(8), 2001, pp. 1439-1442
Intermolecular Pauson-Khand reaction of various 1-alkynes with exo-methylen
e-piperidine and -cyclohexane derivatives was examined to give the title co
mpounds in moderate to good yields.