John D. Spivack

12H-DIBENZO[d,g][1,3,2]DIOXAPHOSPHOCINS: Synthesis and Evidence for Long-Range Coupling to Phosphorus

Abstract The synthesis of the 12H-dibenzo[d,g][1,3,2]dioxaphosphocin ring system from 2,2′-alkylidene bisphenols and phosphorus trichloride is described. The 1H NMR shows evidence for long range through-space coupling of the C-12 methine proton to phosphorus.

2,4,8,10-TETRASUBSTITUTED DIBENZO[d,f][1,3,2]DIOXAPHOSPHEPINS

Abstract The synthesis of the dibenzo[d,f][1,3,2]dioxaphosphepin ring system from substituted biphenyl-2,2′-diols and alkylphosphonous dichlorides is described. The NMR spectral data are consistent with either rapidly interconverting ring conformers or a static non-planar ring conformation.

REACTION OF SEVEN- AND EIGHT-MEMBERED CYCLIC PHOSPHOROCHLORIDITES WITH ALKANOLAMINES

Abstract The reactions of substituted 6-chloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocins and 6-chlorodibenzo[d,f][1,3,2]dioxaphosphepins with primary, secondary and tertiary alkanolamines are described. The primary and sec-aminoalkyl phosphites prepared show no IR or NMR spectroscopic evidence for formation of their tautomeric pentacoordinate form.

6H-DIBENZ[c,e][1,2]OXAPHOSPHORINS: SYNTHESIS AND CHEMISTRY

Abstract The reaction of 1-phenylphenol with phosphorus trichloride at elevated temperature using zinc chloride as a catalyst gave the 6H-dibenz[c,e][1,2]oxaphosphorin 1. The reaction of 1 with the phenols 3a–e gave the corresponding 6-phenoxy derivatives 4a–e. In the case of the sterically hindered phenol 3e, an improved procedure involved the reaction of the sodium phenolate of 3e with 1. The reaction of the benzenethiols 5a–b with 1 using triethylamine as an acid acceptor gave the corresponding derivatives 6a–b.

REACTION OF SEVEN- AND EIGHT-MEMBERED CYCLIC PHOSPHOROCHLORIDITES WITH 3,5-DI-tert-BUTYL-4-HYDROXYBENZYL ALCOHOL: FACILE P[sbnd]C BOND FORMATION

Abstract The reaction of 2,4,8,10-tetra-t-butyl-6-chloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocin (5) or 2,4,8,10-tetra-t-butyl-6-chloro-dibenzo[d,f][1,3,2]dioxaphosphepin (10) with 3,5-di-t-butyl-4-hydroxybenzyl alcohol (7) gave the corresponding P-(4-hydroxybenzyl)phosphonates 9 and 12 rather than the expected phosphites 8 and 11. IR and NMR spectral evidence for the phosphonate structure is discussed.

Sterically hindered phosphonites

Abstract Phosphonochloridous and phosphonous esters were prepared from the reaction of phenylphosphonous dichloride with 2,4-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, and 2,4,6-tri-tert-butylphenol. Various synthetic methodologies, including phase-transfer catalysis, are described and compared. Phosphonous diesters containing two different substituted-phenyl moieties were prepared from phosphonochloridous monoesters. The reaction of O-(2,6-di-tert-butyl-4-methylphenyl)-phenylphosphonochloridite with N-methyldiethanolamine, n-octyl mercaptan, and water was studied and found to give a bisphosphonite, phosphonothioite, and phosphinate, respectively.

SUBSTITUTION OF ARYL HALIDES BY THIOLATE ANIONS

Abstract The reaction of 2.5-di- and 2,3,5,6-tetrachloroterephthalate esters with both alkyl and arylmercaptides in triglyme solvent at room temperature gave the corresponding di- and tetra-substituted alkylthio- and arylthio-substituted terephthalate esters. Similarly, the reaction of both 2,5-di- and 2,3,5,6-tetrachloroterephthalate thioesters with potassium n-octylmercaptide, 2a, in triglyme gave the bis- and tetrakis(n-octylthio)terephthalate thioesters respectively. Both activated and unactivated aryl chlorides reacted with a suspension of a potassium alkylmercaptide in xylene using 18-crown-6 as a solid-liquid phase-transfer catalyst to give the corresponding alkylthio-substituted benzenes. The reaction of 1,2,4-trichlorobenzene with sodium n-dodecylmercaptide in tetraglyme solvent gave 1,2,4-tris(n-dodecylthio)benzene.

Sterically hindered 4-hydroxybenzenesulfenyl chloride: reactivity with trivalent phosphorus esters

Abstract The reaction of 3,5-di-tert-butyl-4-hydroxybenzenesulfenyl chloride, 1, with the trialkyl phosphites 5a–d gave the corresponding S-(3,5-di-tert-butyl-4-hydroxyphenyl)-O,O-dialkyl phosphorothiolates 6a–d. The formation of 6a–d constitutes chemical evidence for the intermediacy of 1 which was previously inferred from spectroscopic evidence.