B. Baccar

PHOSPHO-4-PYRAZOLES. SYNTHESE ET ETUDE SPECTROGRAPHIQUE RMN 1H, 31P ET 13C

Abstract 4-Phosphopyrazoles are prepared with good yield by cyclisation of hydrazone phosphorus compounds and ethylortho formiate. The effects of substitution are investigated on the 13C chemical shifts of pyrazole ring. The magnitude of the coupling constant 1 J pc is in good agreement with the hybridization of the phosphorus atom.

FROM ALLENIC PHOSPHORUS DERIVATIVES TO HETEROCYCLIC COMPOUNDS. SYNTHESIS OF A 1,2,3-DIAZAPHOSPHOLE COMPOUND WITH A STRONGLY POLAR NH GROUP LINKED TO A DICOORDINATE PHOSPHORUS ATOM

Abstract The synthesis of several derivatives containing an allenic group directly linked to a phosphoryl phosphorus atom is described. The addition of alcohol, water, hydrazines to this compounds is studied. The reaction of hydrazones (obtained from allenyldiphenylphosphine oxide) with trichlorophosphine gives rise to derivatives of 1,2,3-diazaphosphole. The hydrazone deriving from unsubstituted hydrazine leads to a compound with an NH group spectroscopically much more acidic than that of pyrrole; this NH group is presumably directly linked to the dicoordinated phosphorus atom.

Synthese De (1,2a)Benzimidazolo-1,3,5,2-triazaphosphorine-2-oxides

The reaction of hexamethylphosphotriamide or methylphosphonic bis(dimethylamide) compounds with amidines derived from N-Benzimidazoyl imidates 1 leads to (1,2a)benzimidazolo-1,3,5,2-tiazaphosphorine-2-oxides 4 in good yields. If the condensation is realized at room temperature, N-phosphonic amidines 3 can be isolated as intermediates. The isolated compounds 2 , 3 , and 4 are identified by spectroscopic methods: IR, 1 H, 13 C, 31 P, NMR, and M.S.

OXYDES DE DIAZAPHOSPHOLINES-1,2,3: SYNTHESE ET ETUDE SPECTROGRAPHIQUE IR ET DE RMN 1H, 31P, 13C

Abstract δ5-3-dimethylamino-3-oxo-1,2,3-diazaphospholines are prepared by cyclisation of bis(dimethylami-no)phosphinallene oxides containing two electrophilic sites in position 1.3 (phosphorus atom and medium carbon allenic) with hydrazine derivatives. Mechanistic explanations of these results have been described by NMR. The IR and the 31P, 13C, 1H chemical shifts of diazaphosphollines oxides are commented.

REACTION DES O, O-DIETHYL OXO-1 ALKANEPHOSPHONATES AVEC LES DERIVES DE L'HYDRAZINE: UNE VOIE DE SYNTHESE DES HYDRAZONES α-PHOSPHONATEES ET DES HYDRAZIDES

Abstract Under the normal conditions, the reaction of hydrazine and methylhydrazine with OO-diethyl 1 oxoalkane phosphonates 1 proceeds by cleavage of the phosphorus-carbon bond and leads to the formation of diethylphosphite 2 and N-acylhydrazide 3 . A procedure has been developed for the synthesis of new primary hydrazone of OO-diethyl 1-oxoalkane phosphonates 4 . A mechanism is proposed. The structure of those compounds 4 was confirmed by NMR and IR spectroscopy.

Sur la regio selectivite de la reaction du benzaldehyde avec les organozinciques issus du γ-bromocrotonate et du γ-bromosenecioate de trimethylsilyle

Abstract The regioselectivity of the reaction of organozinc compounds derived from γ-bromocrotonic and γ-bromosenecioic trimethylsilyl esters, with benzaldehyde is discussed. One-step reactions lead to a majority of α-substituted derivatives, while in two-step reactions, γ-substituted products are exclusively obtained.

ACTION DU REACTIF DE LA WESSON SUR LES HYDRAZONES γ-PHOSPHONATEES: SYNTHESE DE NOUVEAUX DERIVES DE LA Δ5-3-THIOXO-1,2,3-DIAZAPHOSPHOLINE

Abstract The Lawesson reagent (L.R) reacts with phenylhydrazones of ketones γ-disubstituted phosphonates and phosphine oxide 1 to give 1,2,3-diazaphospholine derivatives 2 and 2′. Two diastereomers were obtained in some cases. The structure of the products 2 and 2′ is confirmed by NMR and IR spectroscopy.

ACTION DU REACTIF DE LA WESSON SUR LES HYDRAZONES β-PHOSPHONATEES: SYNTHESE DE Δ5-5-(METHYLENE-PHOSPHINEOXYDE)-3-THIOXO-1,2,3-DIAZAPHOSPHOLINES

Abstract β-Phosphonylhydrazone 1 are considered as reagents in heterocyclic synthesis (Pyrazoles phosphonated, Diazaphospholines oxides). In the present work, we study the reaction of hydrazones β-disubtituted phosphine oxide 1 with Lawesson reagent (L R) to lead to the 3-thioxo-1,2,3-diazaphospholines derivatives 2 . The structure of products 2 is confirmed by NMR and IR spectroscopy.

ACTION DES ENAMINES SUR LES MONOCHLOROPHOSPHINES: SYNTHESE DES β-CETOPHOSPHONATES

Abstract In recent years β-phosphoryl ketones were considered as valuable intermediates in organic synthesis. In the present work we studied the reaction of enamines 1 with monochlorophosphine 2 which led to the β-phosphinoyl cycloalkanones 3. The structure of products 3 was confirmed by NMR and IR spectroscopy.

OXYDES DE N-2-ACYL DIAZAPHOSPHOLINES-1,2,3: SYNTHESE, REACTIVITE ET ETUDE SPECTROGRAPHIQUE IR ET DE RMN 1H, 31P, 13C

Abstract The monoacylhydrazides, as well as hydrazines, react with phosphoallenic derivatives 1 to lead to the δ5-N-2 acyl 3-dimethylamino 3-oxo-1,2,3-diazaphospholine 2 . The reaction of ring opening in δ5-N-2 acyl-3-dimethylamino-3-oxo-1,2,3-diazaphospholine by different alcohols leads to the β-phosphonyl-hydrazide 3 . The structure of products ( 2 and 3 ) is further confirmed by IR, 1H, NMR, 13P NMR, 13C NMR spectra.