X-ray and neutron diffraction studies on HW/sub 2/(CO)/sub 8/(NO)(P(OCH/sub 3/)/sub 3/). A compound with a slightly asymmetric hydrogen bridge bond

Journal Article · Wed Jul 21 04:00:00 EDT 1976 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00431a027· OSTI ID:7356849

Love, R A; Chin, H B; Koetzle, T F; Kirtley, S W; Whittlesey, B R; Bau, R

The molecular structure of HW/sub 2/(CO)/sub 8/(NO)(P(OCH/sub 3/)/sub 3/), prepared by treating HW/sub 2/(CO)/sub 9/(NO) with trimethyl phosphite, was studied with x-ray and neutron diffraction techniques. The presence of the bulky P(OCH/sub 3/)/sub 3/ ligand eliminated the packing disorder problems which occurred in the earlier neutron diffraction analysis of HW/sub 2/(CO)/sub 9/(NO), and allowed the detailed geometry of the WHW region to be examined closely for possible asymmetric features. The structure of HW/sub 2/(CO)/sub 8/(NO)(P(OCH/sub 3/)/sub 3/) consists of W(CO)/sub 5/ and W(CO)/sub 3/(NO)(P(OCH/sub 3/)/sub 3/) fragments joined by a single WHW three-center bond. The nitrosyl ligand was located at an axial position, thereby confirming earlier results on HW/sub 2/(CO)/sub 9/(NO). In the present neutron diffraction study the WHW bond was found to be slightly asymmetric, the difference between the two W--H distances being 0.035 (10) A. The hydrogen atom is closer to the W(CO)/sub 5/ group than to the W(CO)/sub 3/(NO)(P(OCH/sub 3/)/sub 3/) group, as expected since the W(CO)/sub 5/ unit is the more electron-deficient half of the molecule. The rest of the structure is very similar to that of HW/sub 2/(CO)/sub 9/(NO). The molecule has a bent backbone with staggered equatorial ligands, and the hydrogen atom is significantly removed from the point of intersection of the axial W--C and W--N vectors. Crystallographic details for HW/sub 2/(CO)/sub 8/(NO)(P(OCH/sub 3/)/sub 3/): unit cell P anti l; a = 10.012 (7), b = 11.261 (8), c = 9.062 (6) A; a = 90.84 (5), ..beta.. = 90.52 (6), ..gamma.. = 76.35 (4)/sup 0/; V = 992.7 A/sup 3/, Z = 2.

• Research Organization: Univ. of Southern California, Los Angeles
• OSTI ID: 7356849
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 98:15; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
BOND ANGLE
BOND LENGTHS
CARBONYLS
CHEMICAL PREPARATION
COHERENT SCATTERING
DIFFRACTION
MOLECULAR STRUCTURE
NEUTRON DIFFRACTION
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
SCATTERING
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN COMPOUNDS
X-RAY DIFFRACTION