Metallo-Wittig chemistry of an alkylidene to form a terminal titanium oxo complex

Douglas P Solowey; Takashi Kurogi; Brian C Manor; Patrick J Carroll; Daniel J Mindiola

doi:10.1039/c6dt01534d

Metallo-Wittig chemistry of an alkylidene to form a terminal titanium oxo complex

Dalton Trans. 2016 Oct 12;45(40):15894-15901. doi: 10.1039/c6dt01534d.

Authors

Douglas P Solowey¹, Takashi Kurogi¹, Brian C Manor¹, Patrick J Carroll¹, Daniel J Mindiola¹

Affiliation

¹ Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, USA. mindiola@sas.upenn.edu.

PMID: 27338555
DOI: 10.1039/c6dt01534d

Abstract

We report the synthesis and structure of a titanium(iv) benzophenone adduct bearing a terminal oxo ligand, (PNP)Ti = O(OTf)(OCPh₂) (PNP^- = N[2-PⁱPr₂-4-methylphenyl]₂) (2). Complex 2 is readily synthesized in 71% yield from the previously reported titanium alkylidene (PNP)Ti[double bond, length as m-dash]CH^tBu(OTf) (1) and two equivalents of benzophenone, by extruding the olefin Ph₂C[double bond, length as m-dash]CH^tBu. Treatment of benzophenone adduct 2 with a bulky aryloxide salt results in formation of (PNP)Ti[double bond, length as m-dash]O(OAr) (3) (OAr^- = 2,6-bis(diphenylmethyl)-4-tert-butylphenoxide), concurrent with salt elimination and displacement of the benzophenone. Complexes 2 and 3 were characterized by single-crystal X-ray diffraction and a variety of spectroscopic techniques, including NMR, UV-Vis-NIR spectroscopies, and TD-DFT calculations.