Microwave spectrum and structure of dimethylaminodifluorophosphine PF2N(CH3)2

Gas-phase structures of aminodifluorophosphines determined using electron diffraction data and computational techniques

“…(The total angle around N was thought to be 348.4 • .) This is in contrast to the microwave structure 16 and an X-ray analysis of the solid phase, 18 both of which show planar structures, as did our calculations and refinement. To probe how easily 4 can become nonplanar, calculations were performed (MP2/6-311+G*) where the geometry of the molecule was optimised as the C-N-P-C torsion angle was stepped from 140 to 220 • .…”

“…It was assumed that the N(CH 3 ) groups had C 3v local symmetry and that the PF 2 group had a plane of symmetry. A microwave spectrum 16 for (PF 2 )N(CH 3 ) 2 had been recorded and rotational constants, corrected using SHRINK, were included in the refinement as extra data. The refinement was repeated, this time excluding the rotational constants.…”

The crystal and molecular structures of six- and seven-membered-ring organophosphorus compounds. 1,3,2-Dioxaphosphorinanes and 1,5-dihydro-1,4,3-benzodioxaphosphepins

“…The plane of the N-C bonds bisects the ring O-P-O angle and one N-C bond eclipses the P=S double bond. When such a stereochemistry exists around the P-N bond, the N is planar (Morris & Nordman, 1969;Brittain, Smith, Lee, Cohn & Schwendeman, 1971;Forti, Damiani & Favero, 1973;Camerman & Camerman, Table 8. Least-squares symmetry-plane equations for (I), (III) and (IV) and distances (A) of the ring atoms to the symmetry planes 2-Thiono-2,5,5-trimethyl-1,3,2-dioxaphosphorinane (I) -0.6816X + 0.3855Y -0.6220Z -0.0732 = 0 O(1) 1.242 0(3)--1-251 S -0.007 C(7) 0.005 C(6) 1.244 C(4)-1.244 P 0.003 C(5) -0.002 C(7)-0.002 C(8) 0.003 3-Thiono-3-methyl-1,5-dihydro-2,4,3-benzodioxaphosphepin (II I) 0.7517X -0.0370Y-0.6585Z -2.1699 = 0 O(2)-1.2740 0(4) 1.2519 C(11)-1.4426 C(8) -1.3141 C(1)-1.5009 C(5) 1.4522 C(9) -0.7675 C(10) 0.6127 C(7)-0.7507 C(6) 0.6591 3-Thiono-3-N-dimethylamino-1,5-dihydro-2,4,3-benzodioxaphosphepin (IV) 0.6609X -0.6724Y-0.3334Z + 11.0579 -0 0(2) 1.240 0(4)-1.257 C(8)…”

The crystal and molecular structures of 2-thiono-2-N-(diisopropylamino)-1,3,2-dithiophosphorinane and of 2-thiono-2-aziridino-1,3,2-dithiaphosphorinane

“…Such planarity is common in amino-phosphorus compounds in which an acyclic amino group is in ct position to a three- (Morris & Nordman, 1969;Brittain, Smith, Lee, Cohn & Schwendeman, 1971;Forti, Damiani & Favero, 1973) or four-coordinate (Camerman & Camerman, 1973; The plane of the C-N bonds bisects the S(1)-P-S(3) angle and N-C(9) eclipses the P=S double bond. This stereochemistry around the P--N bond seems to be quite general in three-and four-coordinated P compounds and can explain the equatorial orientation of the P-N bond.…”