Reaction of CPNs and Related Compounds

In the course of the study, Nakamura and Isobe have developed a new synthetic method for substituted cyclopentadienone acetals (CPDNAs) 79 employing 

Recent developments in experimental techniques or protective group manipulation have enabled several heterofulvenes to be isolated in pure form. 

The reaction of tetrachlorocyclopropene 59 with the bulky (2,4,6-tri-fert-butylphenyl)phosphine 91 in the presence of 2,6-diisopropylaniline as a base afforded a diastereomeric mixture of 4-phosphatriafulvenes 92 as a stable orange solid in 66% yield. Oxidation of 92 with iodine afforded the first stable 

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