01057nas a2200169 4500008004100000245015900041210006900200260000800269300001600277490000600293520037500299100001600674700002200690700002000712700002400732856013100756 2006 eng d00aNovel synthesis of highly functionalized pyrazolines and pyrazoles by triphenylphosphine mediated reaction of dialkyl azodicarboxylate with allenic esters0 aNovel synthesis of highly functionalized pyrazolines and pyrazol cMAY a2213–22160 v83 a

Reaction of the Huisgen zwitterion, derived from triphenylphosphine and dialkyl azodicarboxylate, with allenic esters affords highly functionalized pyrazolines and pyrazoles. The crystal structure of pyrazoline derivative 7a showed extensive C−H···O interactions. Pyrazole formation proceeds via a novel nitrogen to carbon migration of the carboalkoxy group.

1 aNair, Vijay1 aBiju, Akkattu, T.1 aMohanan, Kishor1 aEringathodi, Suresh uhttps://library.ncl.res.in/content/novel-synthesis-highly-functionalized-pyrazolines-and-pyrazoles-triphenylphosphine-mediated