Unusual Hydrolysis Reactions of <i>cis</i>-Bis((2,2‘-biphenylylene)phosphochloridite ester)tetracarbonylmolybdenum(0)
作者:Houston Byrd、Jeremiah D. Harden、Jennifer M. Butler、Michael J. Jablonsky、Gary M. Gray
DOI:10.1021/om049851w
日期:2004.6.1
The hydrolysis of cis-Mo(CO)(4)(2,2'-C12H8O2PCl)(2) (1) in the presence of excess triethylamine and water yields [(C2H5)(3)NH](2)[CiS-Mo(CO)(4)(2,2'-C12H8O2PO)(2)] (2). This complex is in equilibrium with [(C2H5)(3)NH] [cis-Mo(CO)(4)(2,2'-C12H8O2PO)(2,2'-C12H8O2POH)] (3) and free triethylamine in solution. The hydrolysis of 1 with a stoichiometric amount of triethylamine and water yields only 3. A Scatchard plot for the reaction of 3 and triethylamine to form 2 at 25 degreesC gives an equilibrium constant of 5.8 x 10(-3) for the reaction. Fitting the variable-temperature P-31H-1} NMR spectra of a CD2Cl2 solution of 3 and 0.5 equiv of triethylamine using the gNMR program gives an activation energy of 47.4 kJ/mol for the reaction. The diastereomers of 3 crystallize with very different morphologies, allowing the X-ray crystal structures of both enantiomers to be determined. The 3R*R* diastereomer crystallizes in the noncentrosymmetric P2(1)2(1)2(1) space group, but the 3R*S* diastereomer crystallizes in the centrosymmetric P2(1)/c space group. The most interesting feature of the structures of 3R*R* and 3R*S* is the strong, intramolecular hydrogen bonding between the 2,2'-C12H8O2POH and 2,2'-C12H8O2PO- ligands that result in short O-O distances in both enantiomers (2.520(6) Angstrom in 3R*R* and 2.373(11) Angstrom in 3R*S*). The hydrogen bonding in both diastereomers is asymmetric, in contrast to previous speculation in the literature.