C(sp3)−H Oxidative Addition and Transfer Hydrogenation Chemistry of a Titanium(II) Synthon: Mimicry of Late‐Metal Type Reactivity. (6th October 2016)

• Record Type: Journal Article
• Authors: Aguilar‐Calderón, J. Rolando; Metta‐Magaña, Alejandro J.; Noll, Bruce; Fortier, Skye
• Is Part Of: Angewandte Chemie. Volume 128:Number 45(2016)
• Page Start: 14307
• Page End: 14311
• Publication Date: 2016-10-06
• Subjects: C-H-Aktivierung -- N-Liganden -- Reduktionen -- Titan -- Transferhydrierungen; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201607441
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Two‐electron reduction of the Ti IV compound ( ket guan)(Im Dipp N)Ti(OTf)2 (3 ) gives the arene‐masked complex ( ket guan)(η 6 ‐Im Dipp N)Ti (1 ) in excellent yield. Upon standing in solution, 1 converts to a Ti IV metallacycle (4 ) through dehydrogenation of a pendant isopropyl group. Spectroscopic evidence shows this transformation initially proceeds via the oxidative addition of a C(sp 3 )−H bond and can be reversed upon exposure of4 to H2 . Interestingly, treatment of1 with cyclohexene gives cyclohexane and4 via a titanium‐mediated transfer hydrogenation reaction, a process that can be extended to catalytically hydrogenate other unsaturated hydrocarbons under mild conditions. These results, rare for the early‐metals, suggest1 possesses chemical characteristics reminiscent of noble, late‐metals.