Bernard Garrigues

The carbonyl-Diels-Alder reaction catalyzed by bismuth (III) chloride

Abstract In presence of bismuth (III) chloride, a carbonylated electrophile (ethyl mesoxalate or glyoxylate) and usual diene led selectively (65 to 100%) the hetero carbonyl-Diels-Alder reaction with the ene reaction product. BiCl 3 exhibits strong catalytic activity and, compared with previous literature, reacts under mild conditions.

Potassium Fluoride on Alumina: Dry Condensation of 3-Phenylisoxazol-5-one with Aldehydes Under Microwave Irradiation

Abstract 3-Phenylisoxazol-5-one (2) and aromatic aldehydes were condensed to 3-phenyl-(4-arylmethylene) isoxazol-5-one (3) in the presence of Al2O3-KF without solvent under microwave irradiation.

Improved Synthesis of Oxazoline Under Microwave Irradiation

Abstract Oxazolines have been prepared under microwave irradiation by two different ways. In a first one, imino ether hydrochlorides have been reacted with amino alcohols in the presence of alumina supported potassium fluoride, in an open vessel. In a second one, amino alcohols are directly reacted with imino ethers in a closed vessel.

Improved Synthesis of Oxadiazoles Under Microwave Irradiation

Abstract Abstract Amidoximes (1) reacted with isopropenyl acetate in presence of KSF under microwave irradiation and gave 1,2,4-oxadiazoles (2). 1,2,4-Oxadiazoles (4) can also be obtained by microwave irradiation from O-acylamidoximes (3) adsorbed on Alumina. 1,3,4-Oxadiazoles (6) were obtained by irradiation of bis (acyl) hydrazines (5) in thionyl chloride.

Spirophosphoranylation d'α-aminoacides—I : Preparation et tautomerie1

Resume Une vingtaine de spirophosphoranes nouveaux (Tableaux 1 et 2) ont ete prepares en faisant reagir les &alpha-aminoacides sur des composes du phosphore tricoordine possedant un groupement partant convenable. Dans le cas du compose 1i , un equilibre chaǐne-cycle P III P v a ete mis en evidence.

Spirophosphoranes a liaison P-OH. Synthese, tautomerie

Abstract Spirophosphoranes with a P-OH bond have been prepared as free acid (compound 5c), triethylammonium salts (compounds 2c–6c), or adducts 1 1 with DMF (compounds 5c and 6c). The ionic feature of triethylammonium salts of compounds 1c–6c, shows that these Spirophosphoranes are relatively strong Bronsteds acids. Tautomeric equilibrium phosphoric ester—phosphorane with a P-OH bond [Scheme 9), shown in many cases, has been studied by means of 31PN, MRspectroscopy. Influence of factors ruling this equilibrium is analysed. Some elements of dynamic stereochemistry are examined.

LA REACTION DE DIELS-ALDER CATALYSEE PAR LES SELS DE BISMUTH (III)

We have studied the Diels–Alder reaction from the dienes (1–3) and dienophiles (4–6), catalyzed by bismuth triflate and bismuth chloride. We compared these two catalysts with SnCl4, ZnI2, AlCl3 and Cu(BF4)2 respectively. With bismuth derivatives we noted no polymerisation, a better yield and a good selectivity in cycloadditions.

Synthese de derives mono- et bicycliques du bore tetracoordonne et des α-aminodiacides

Triethyl- and triphenyl-boranes react with α-aminodiacids, R1N(CHR2COOH)2 (R1 = H, Me, PhCH2; R2 = H, Me), leading to mono- and bi-cyclic compounds. Depending on the experimental conditions and the substitution of the aminodiacid, either can be isolated. Eight compounds were prepared.

THIOPHENE-CONTAINING MACROCYCLES DERIVED FROM [2 + 2] CYCLIZATIONS

Abstract Tetra ester macrocycles 7, 8, carboxamide macrocycles 9a, b and Schiff base macrocycles 10, 12a, b containing two or four thiophene moieties are obtained from 2,5-thiophene dicarbonylchloride or various aldehydes and esters derived from thiophene.

Un exemple d'equilibre tautomere phosphite phosphorandure

Resume A compound has been isolated whose elemental analysis, nmr and IR data are consistent with an equilibrium phosphoranide phosphite.