Syntheses and experimental studies on the relative stabilities of spiro, ansa, and bridged derivatives of cyclic tetrameric fluorophosphazene

Citation
Aj. Elias et al., Syntheses and experimental studies on the relative stabilities of spiro, ansa, and bridged derivatives of cyclic tetrameric fluorophosphazene, INORG CHEM, 40(9), 2001, pp. 2120-2126
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Inorganic & Nuclear Chemistry
Journal title
INORGANIC CHEMISTRY
ISSN journal
0020-1669 → ACNP
Volume
40
Issue
9
Year of publication
2001
Pages
2120 - 2126
Database
ISI
SICI code
0020-1669(20010423)40:9<2120:SAESOT>2.0.ZU;2-7
Abstract
Reactions of (CF2CH2OSiMe3)(2) and CF2(CF2CH2OSiMe3)(2) with N4P4Fdelta (1) in a 1:2.5 molar ratio resulted in the formation of monospiro compounds [( CF2CH2O)(2)PN] (F2PN)(3) (2) and [CF2(CF2CH2O)(2)PN](F2PN)(3) (4) as well a s the intermolecular bridged compounds F7N4P4OCH2CF2CF2CH2OP4N4F7 (3) and F 7N4P4OCH2CF2CF2CF2CH2-OP4N4F7 (5). An equimolar reaction of dilithiated 1,3 -propanediol with 1 resulted in the 1,3-ansa-substituted compound CH2(CH2O) (2)[P(F)N](2)(F2PN)(2) (6) as the major product in good yield. However, an analogous reaction of the dilithiated 1,3-propanedithiol with 1 gave only t he spirocyclic compound CH2(CH2S)(2)(PN)(F2PN)(3) (8). The molecular struct ures of 2 and 6 were determined by single-crystal X-ray diffraction. In the presence of catalytic amounts of CsF in THF, the bridged compound 3 was co nverted to the spirocyclic compound 2 while the 1,3-ansa compound 6 under s imilar conditions transformed into the monospiro-substituted compound CH2(C H2O)(2)(PN)(F2PN)(3) (7). These transformations were monitored by time-depe ndent F-19 and P-31 NMR studies.