Oligomerization of phosphaalkynes mediated by bulky N-heterocyclic carbenes: avenues to novel phosphorus frameworks

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 48; no. 38; pp. 14242 - 14245
• Main Authors: Liu, Liu Leo, Zhou, Jiliang, Kim, Youngsuk, Cao, Levy L, Stephan, Douglas W
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 01.10.2019
• Subjects: Carbenes; Crystallography; Oligomerization; Phosphaalkynes
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c9dt03185e

Reactions of RC&z.tbd;P (R = t Bu or Ad (admantyl)) with NHCs (SIMes, 1a ; IMes, 1b and IDipp, 1d ), leading to 1,2,3-triphosphetenes 2 and 3 , a triphosphole 4 , and a di-1,2-dihydro-1,2-diphosphete-substituted diphosphene 5 , are reported. Compound 5 represents a novel P 6 chain framework, as well as a newly discovered phosphaalkyne hexamer stabilized by two NHCs. Computational investigations suggest that the weak π-accepting ability of NHCs results in low stability of the initially formed 2 H -phosphirenes, thus facilitating spontaneous oligomerization reactions. Such oligomerizations are highly susceptible to the electronic property and steric bulk of NHCs. Reactions of RC&z.tbd;P (R = t Bu or Ad (admantyl)) with NHCs (SIMes, 1a ; IMes, 1b and IDipp, 1d ), leading to 1,2,3-triphosphetenes 2 and 3 , a triphosphole 4 , and a di-1,2-dihydro-1,2-diphosphete-substituted diphosphene 5 , are reported.