Abstract
The compound [Pt3(µ-CO)3{P(C6H11)3}3] reacts with 3 and 5 mol of 2,6-xylyl isocyanide, CNC8H9, to give [Pt3(µ-CO)(µ-CNC8H9)2(CNC8H9){P(C6H11)3}2](1) and [Pt3(µ-CNC8H9)3(CNC8H9)2{P(C6H11)3}](2) respectively. The molecular structures of both compounds have been determined by single-crystal X-ray techniques using diffractometer data. Compound (1) crystallises in the monoclinic space group P21/n with four units of formula [Pt3(µ-CO)(µ-CNC8H9)2(CNC8H9)-{P(C6H11)3}2]·0.5C6H6in a cell of dimensions a= 15.431(5), b= 15.810(3), c= 28.489(19)A, and β= 95.22(4)° and (2) in the monoclinic space group P21/a with four formula units in a cell of dimensions a= 16.412(2), b= 18.444(2), c= 24.383(2)A, and β= 90.155(9)°. The structures of both molecules are approximately equilateral triangles of Pt atoms with Pt–Pt distances in the range 2.618(1)–2.654(1)A. The bonded ligand atoms are approximately coplanar with the metal triangles and 31P-{1H} and 195Pt-{1H} n.m.r. studies suggest that both solid-state structures are retained in solution. When intermediate mol ratios of isocyanide were added to [Pt3(µ-CO)3{P(C6H11)3}3] then mixtures of (1), (2), and starting material only were obtained. No evidence for the formation of symmetrical products of the type [Pt3(µ-CNC8H9)3{P(C6H11)3}3] was obtained. Examination of the molecular structures of (1) and (2) has formed a basis for rationalising the observed stoicheiometries. The bridging isocyanide ligands are severely bent about the nitrogen atoms and their steric requirements are incompatible with the presence of P(C6H11)3ligands on both of the metal atoms being bridged. Consequently, replacement of bridging CO by the isocyanide labilises an adjacent terminal P(C6H11)3ligand. Compound (2) has also been synthesised by sodium-amalgam reduction of [Pt(CO)Cl2{P(C6H11)3}] in the presence of an excess of isocyanide ligand.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of the Chemical Society, Dalton Transactions
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.