Abstract
Reactions of bis(iminophosphoranyl)methane, CH2(PPh2=N-aryl)2, (BIPM; 1a,b) or 1,1-bis(iminophosphoranyl)ethane (1,1-BIPE; 1c) with Pd-and Pt-dichlorides containing weakly coordinating ligands (L) such as nitriles or cyclo-octadiene, afforded several products depending on the reaction time, type of ligand (1a-c) or nature of the metal. The first reaction observed is a metal-assisted tautomerization of BIPM to aryl-N=PPh2-CH=PPh2-NH-aryl. When BIPM reacts with PdCl2(L)2, exclusive formation of the C,N-chelate PdCl2{CH(PPh2=N-aryl)(PPh2-NH-aryl)} (2a,b) is observed, whereas with 1,1-BIPE (1c) a product mixture consisting of a C,N-chelate (2c) and an N,N′-chelate (3) is found. Orthometallation of the four-membered palladacycle (2) took place upon heating, giving the five-membered palladacycle [PdCl2{2-C6H4-PPh(NH[-pTol)-C′H-PPh2(NH-pTol)}-C,C′] (4). The molecular structure of 4 has been determined by X-ray crystallography. Reactions of BIPM (1a,b) with PtCl2(RC≡N)2 (R = phenyl, p-tolyl) afforded entirely different products: the six-membered platinacycles [PtCl(RC≡N){aryl-N=C(R)-N=PPh2-CH=PPb2-NH-aryl}-C,N]Cl (5) and [PtCl2{aryl-N=C(R)-N=PPh2-CH=PPh2-NH-aryl}-C,N] (6), due to an unexpected 2 + 2 cycloaddition of a nitrile with a P=N group.
Original language | English |
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Pages (from-to) | 263-276 |
Number of pages | 14 |
Journal | Journal of Organometallic Chemistry |
Volume | 527 |
Issue number | 1-2 |
Publication status | Published - Jan 11 1997 |
Keywords
- 2 + 2 cycloadditions
- Nitriles
- Palladium
- Phosphinimines
- Platinum
ASJC Scopus subject areas
- Biochemistry
- Inorganic Chemistry
- Organic Chemistry
- Physical and Theoretical Chemistry
- Materials Chemistry