Claude Charrier

Characterisation of the parent phosphole and phospholyl anion and some of their C-substituted derivatives by 1H and 13C NMR spectroscopy

The parent phosphole and phospholyl anion as well as some C-substituted derivatives have been characterized by 1H and 13C NMR spectroscopy for the first time; the two most noteworthy features are the absence of 3J(H-P-C-H) couplings for the phospholes and the huge 1J(CP) couplings for the phospholyl anions.

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.

Another synthesis of 1,3-diphospholyl anions and their use for the preparation of 1,1′,3,3′-tetraphosphaferrocenes

Abstract A new series of 1,3-diphospholyl anions has been obtained from 1,3-diphenyl-1,3-diphosphol-4-enes via the metallation of the PCH2P unit by n-butyllithium followed by the cleavage of the two PPh bonds by lithium in THF. These anions have been allowed to react with the bis-η6-p-xylene)iron dication to prepare novel 1,1′,3,3′-tetraphosphaferrocenes which have been characterized by X-ray crystal structure analysis.

Extraction and identification of a plasticizer, di-(2-ethylhexyl)phthalate, from a plastic bag containing contaminated corn

Residues of di-(2-ethylhexyl)phthalate (DEHP) were extracted along with deoxynivalenol (DON) from plastic bags containing corn contaminated byFusarium graminearum. The concentration/extraction of this residue involved a series of silica gel-400 chromatography columns followed by purification by semi-preparative column chromatography, using hexane/dichloromethane as the mobile phase. The purified product was identified by NMR (1H and13C) and mass spectrometry. Quantification of DEHP was also done by high performance liquid chromatography (HPLC).

The 1,2-dihydro-1,2-diphosphete-1,4-diphosphadiene equilibrium. X-ray structures of [μ2,μ2,η1,η1-(Ph)8C4P4]W2(CO)6 and [μ1,μ1-(Ph)4C2P2]W2(CO)10

Abstract As its P2W2(CO)10 dicomplex, the ring of 1,2,3,4-tetraphenyl-1,2-dihydro-1,2-diphosphete undergoes a reversible conrotatory opening to give the corresponding 1,4-diphosphadiene dicomplex which can be trapped as [4+2] cycloadducts with N-phenylmaleimide, maleic anhydride, acrylonitrile and benzaldehyde. X-ray crystal structure analysis indicates a weakening of the PP bond of the 1,2-dihydro-1,2-diphosphete upon complexation: the PP bond length increases from 2.248(1) A in the free ring to 2.281(3) A in the complex explaining why this reversible opening takes place only in the complex.

2-Diphenylphosphino-1,3-diphospholide anions

The title compounds are easily obtained in four steps from 4,5-disubstituted 1,3-diphenyl-1,3-diphosphacyclopent-4-enes (1). Metallation of the PCH2P unit of 1 followed by reaction with Ph2PCl allows a diphenylphosphino group to be grafted onto 1 at the C2 carbon. After removal of the remaining C2H proton by a base, selective cleavage of the two P1Ph and P3Ph bonds by lithium in THF affords the corresponding 2-diphenylphosphino-1,3-diphospholide ions (5). In one case, the reaction of n-butyllithium with 1a leads to an opening of the five-membered ring via a nucleophilic attack at phosphorus. A bis-(phosphino)methanide ion (8) is thus obtained. Its chemistry has been investigated briefly.

ω,ω′-Diphospholylalkanes

Abstract The reaction of compounds (1) with lithium or sodium can lead to different results depending on the length of the exocyclic chain : when n=1,2 or 4, we observe cleavage of both exocyclic P-C bonds, giving pure phospholyllithium or sodium.