Kristall- und Molekülstruktur von cis-Dithiodihydrazido-dimetaphosphorsäure-diphenylester

Abstract

Crystals of the title compound, C6Hs-O-(S)P(NH-NH)zP(S)-O-C6Hs, are monoclinic, a= 18"559 (7), b= 7.334 (2), c= 13-073 (5) A, ,8= 113.24 (3) °, space group C2/e, Z=4. The crystal structure was determined from X-ray diffraction data collected on a four-circle diffractometer by means of Patterson and difference Fourier syntheses and was refined by the method of least squares to an R value of 0.037 for 1345 reflexions. The molecules possess point symmetry 2. The phosphorus-hydrazine heterocycle has a twist conformation with P-N-N angles of 120.3 and 116-5 °, almost equal to those found in the chair conformation of the trans isomer. The N-P-N angle of 101"4 ° is smaller than in the chair form. The two P-N bonds (1-645 and 1.662 ~) are shorter than expected for single bonds. The N-N bond length is 1.400/~,. The two structures of the title compound and its isomer are the first example of twist and chair conformations being confirmed by X-ray analysis for a pair of cis-trans isomers of a sixmembered 1,4-substituted saturated ring system.

Synthèse, structure cristalline et moléculaire du trimethyl-4,6,9 hexaza-1,3,4,6,7,9 phospha-5 tricyclo [3.3.1.13,7] decane

“…Cette différence provient, bien évidem-ment, des contraintes stériques imposées par la structure adamantane. (2) 105 (1) 115 (2) Autres hétérocycles possédant (e) 1,64 à 1,40 à 92,7 à 111,1 á l'enchaînement P -Ν -Ν 1,«87 1,495 107 120,3 (a) Grand et al, 1980 (b) Adamson et al, 1970;Brittain et al, 1971 ;Grand et al, 1980(c) Clardy et al, 1974Prange et al, 1977;Shaw, 1978(d) Van Doorme et al, 1971(e)Giljeetal., 1972Engelhardt et al, 1975;Cordes et al, 1975;Nöthet al, 1976;Ullmanet al, 1976;Engelhardt et al, 1976;Grand et al, 1980;Jaud et al, 1980 Il n'a pas été possible de mettre en évidence l'inversion des azotes en α du phosphore par une étude de résonance magnétique protonique en tempéra-ture variable du composé i en solution dans le chloroforme deutérié. Ceci signifie que la barrière d'inversion de ces azotes est fort.…”

Bis(hexahydro-1-pyridazinyl)thiophosphorsäure-O-phenylester, C14H23N4OPS

“…So liegen z.B. ges~ittigte anorganische Sechsringe mit Hydrazineinheiten als Ringbaustein unter bestimmten Voraussetzungen in der ungewfhnlichen TwistKonformation vor, was zu relativ grossen Torsionswinkel um die N--N-Bindungen ffihrt (Viertel & Engelhardt, 1984;Engelhardt, Bringer & Viertel, 1983;Engelhardt & Viertel, 1982a, b;Engelhardt & Hartl, 1976). Demgegeniiber wurde in entsprechenden ges~ittigten organischen Heterocyclen, z.B.…”

Structure of the cis isomer of a six-membered phosphorus phenylhydrazine ring

“…(2) 1.648 (2) Phenyl group C---C (mean) 1-38 The comparatively short N--N bond length together with the sum of the bond angles around N(1) (356.5 °) shows that the bonding state at the N(1) atom tends to sp 2 hybridization. The shortest N--N distance in a phosphorus hydrazine heterocycle (1.400 A) has been found in cis-3,6-dithioxo-3,6-diphenoxy-1,2,4,5-tetraaza-3a 5,6a 5-diphosphacyclohexane (Engelhardt & Hartl, 1976), which has an angular sum of 359.3 ° .…”