CONFORMATIONS OF (ARYLOXY)-LAMBDA(3)-CYCLOTRIPHOSPHAZANES - SINGLE-CRYSTAL X-RAY STRUCTURES OF [ETNP(OR)](3) [R = C6H4BR-2 (CIS), C6H3ME2-2,6 (TRANS)]

Authors
THIRUPATHI N KRISHNAMURTHY SS NETHAJI M
Citation
N. Thirupathi et al., CONFORMATIONS OF (ARYLOXY)-LAMBDA(3)-CYCLOTRIPHOSPHAZANES - SINGLE-CRYSTAL X-RAY STRUCTURES OF [ETNP(OR)](3) [R = C6H4BR-2 (CIS), C6H3ME2-2,6 (TRANS)], Phosphorus, sulfur and silicon and the related elements, 123, 1997, pp. 263-276
Citations number
16
Journal title
Phosphorus, sulfur and silicon and the related elements → ACNP
ISSN journal
10426507
Volume
123
Year of publication
1997
Pages
263 - 276
Database
ISI
SICI code
1042-6507(1997)123:<263:CO
Abstract
The reaction of the lambda(3)-cyclotriphosphazane, (EtNPCl)(3) with 2- bromo or 2-nitro phenol in the presence of diazabicyclooctane yields a cis-trans isomeric mixture of [EtNP(OC6H4X-2)](3) (X = Br or NO2) fro m which the cis-[EtNP(OC6H4Br-2)](3) or trans-[EtNP(OC6H4NO2-2)](3) is isolated in a pure state by fractional crystallisation. The two compo unds have been characterised by elemental analysis and NMR (P-31, C-13 , and H-1) spectroscopic data. Variable temperature (303-363 K) P-31 N MR studies on cis-[EtNP(OC6H4Br-2)](3) indicate its slow conversion to the trans-analogue with increasing temperature. The structure of cis- [EtNP(OC6H4Br-2)](3) and the previously known trans-[EtNP(OC6H3Me2-2,6 )](3) have been determined by single crystal X-ray analysis. The six-m embered P3N3 ring adopts a chair and a twist conformation in cis-[EtNP (OC6H3Br-2)](3) and trans-[EtNP(OC6H3Me2-2,6)](3) respectively. The st ructural features are compared with those observed for other lambda(3) -cyclotriphosphazanes.