176895-47-9

Upstream product

• 176895-47-9 cis-[Pt(CH3)(α(2)-(diisopropylphosphino)isodurene)(P((i)Pr)2(CH2C6H2(CH3)2CH2))] 
• 176756-28-8 α²-(diisopropylphosphino)isodurene 

Downstream Products

• 176756-30-2 [Pt(P((i)Pr)2(CH₂C₆H₂(CH₃)2CH₂))2] 
• 176756-29-9 trans-[Pt(CH3)(α(2)-(diisopropylphosphino)isodurene)(P((i)Pr)2(CH2C6H2(CH3)2CH2))] 
• 213133-42-7 trans-[Pt(H)(α(2)-(diisopropylphosphino)isodurene)(P((i)Pr)2(CH2C6H2(CH3)2CH2))] 
• 213133-43-8 trans-[Pt(H)2(α(2)-(diisopropylphosphino)isodurene)2] 

Relevant academic research and scientific papers

Exclusive C-Si bond formation upon reaction of a platinum(II) alkyl with silanes

An unusual, highly selective C-Si coupling reaction takes place upon treating the platinum(II) alkyl complex cis-(DIPPIDH)(DIPPID)PtMe (2) (DIPPIDH = α2-(diisopropyl-phosphino)isodurene, 1) with HSiR3 (R3 = Et3, EtMe2, Me2Ph), leading to formation of MeSiR3 and the hydrido complex trans-(DIPPIDH)(DIPPID)PtH (5). The overall process involves activation of a Si-H bond, reverse-cyclometalation of the phosphine ligand DIPPIDH (1), and C-Si elimination. The resulting thermally stable platinum(II) hydride complex 5 was independently prepared by thermolysis of a platinum(II) dihydride, trans-(DIPPIDH)2PtH2 (6), which was obtained by reaction of 2 with H2. In the absence of silane, the cis complex 2 isomerizes thermally to trans-(DIPPIDH)(DIPPID)PtMe (3), which does not react productively with silanes. Our results indicate that opening of the metallacycle of 2 by benzylic C-H formation is kinetically preferred over formation of CH4 or CH3SiR3.

Consecutive cyclometalation by platinum(II)

The mechanism of the selective formation of the new benzylic mono- and bicyclometalated platinum(II) complexes 2a,b and 3b has been studied. Monitoring the initial sp3 C-H activation of the ligand DIPPIDH (α2-(diisopropylphosphino)isodurene; 1) and (1,5-cyclooctadiene)dimethylplatinum(II) ((COD)PtMe2) at room temperature by 31P{1H} NMR reveals that, after displacement of 1,5-cyclooctadiene, the complex cis-(DIPPIDH)(DIPPID)-PtMe (2a) is formed selectively by oxidative addition of a benzylic C-H bond and subsequent reductive elimination of CH4. This reaction is controlled by electronic factors. Heating of 2a results in isomerization to the thermodynamically more stable isomer trans-(DIPPIDH)-(DIPPID)PtMe (2b) as well as the formation of the double-C-H activated complex trans-(DIPPID)2Pt (3b) with liberation of CH4 in parallel pathways. Continuous heating results in the quantitative formation of the thermally stable 3b. Mechanistically, the second C-H activation proceeds analogously to the first one. The molecular structure of 3b, possessing two six-membered metallacycles, two methylene bridges, and two phosphines in mutually trans positions, was determined by complete single-crystal diffraction studies.