Maurice Santelli

Efficient coupling of heteroaryl halides with arylboronic acids in the presence of a palladium–tetraphosphine catalyst

Abstract Cis , cis , cis -1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane:·1/2[PdCl(C 3 H 5 )] 2 system catalyses the Suzuki cross-coupling of heteroaryl halides with a range of arylboronic acids with very high ratio substrate/catalyst in good yields. Substrates such as pyridines, quinolines, thiophenes, an indole, pyrimidines or a furane have been used successfully.

Palladium-Catalysed Direct 3- or 4-Arylation of 2,5-Disubstituted Pyrrole Derivatives: An Economically and Environmentally Attractive Procedure

Straight to the point: The direct 3- or 4-arylation of pyrrole derivatives through C--H bond activation proceeds in moderate to good yields using Pd(OAc)(2) as catalyst. In contrast to classical coupling procedures, the preparation of an organometallic derivative is not required and the major by-products are AcOH/KBr instead of metallic salts.

Heck reaction with heteroaryl halides in the presence of a palladium-tetraphosphine catalyst

Abstract cis , cis , cis -1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/ 1 2 [PdCl(C3H5)]2 system catalyses efficiently the Heck reaction of heteroaryl halides with n -butyl acrylate, styrene, vinylpyridine and vinyl ether derivatives. High turnover numbers can be obtained for the reactions with halo pyridines, quinolines, furans or thiophenes.

Efficient coupling of heteroaryl bromides with arylboronic acids in the presence of a palladium-tetraphosphine catalyst

The cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane/[PdCl(C3H5)]2 system catalyses the Suzuki cross-coupling of heteroaryl bromides with arylboronic acids with a very high substrate/catalyst ratio in good yields. Substrates such as pyridines, quinolines, thiophenes, an indole, a pyrimidine or a furane have been used successfully.

Heck reaction of aryl halides with linear or cyclic alkenes catalysed by a tetraphosphine/palladium catalyst

Abstract cis , cis , cis -1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/[PdCl(C 3 H 5 )] 2 system catalyses efficiently the Heck reaction of aryl halides with linear alkenes such as pent-1-ene, oct-1-ene or dec-1-ene. Selectivities up to 70% in favour of E -1-arylalk-1-ene isomers can be obtained. In the presence of cyclic alkenes the selectivities of the reactions strongly depends on the ring size. Addition to cyclohexene or cycloheptene led mainly to 1-arylcycloalk-3-ene derivatives. On the other hand, addition to cyclooctene led to 1-arylcycloalk-1-ene adducts.

A new efficient tetraphosphine/palladium catalyst for the Heck reaction of aryl halides with styrene or vinylether derivatives

Abstract cis , cis , cis -1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/[PdCl(C 3 H 5 )] 2 system efficiently catalyses the Heck reaction of aryl halides with styrene and vinylether derivatives. High turnover numbers can be obtained for the reaction of several aryl halides with styrene and styrene derivatives. Lower turnover numbers have been observed in the presence of vinylethers.

Tetraphosphine/palladium-catalysed Suzuki cross-coupling with sterically hindered aryl bromides and arylboronic acids

cis,cis,cis-1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/[PdCl(C3H5)]2 system efficiently catalyses the Suzuki cross-coupling of sterically hindered substrates. Very high turnover numbers can be obtained for the coupling of sterically hindered aryl bromides with benzeneboronic acid or for the coupling of bromobenzene with sterically hindered arylboronic acids. On the other hand the formation of tri-ortho-substituted biaryl adducts requires higher catalyst loading.

Palladium-tetraphosphine complex: an efficient catalyst for the coupling of aryl halides with alkynes

The cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)-cyclopentane-[PdCl(eta3-C3H5)]2 system catalyses the coupling of aryl halides with alkynes with very high ratios of substrates-catalyst in good yields; a turnover number of 2600000 can be obtained for the reaction of 4-trifluoromethylbromobenzene with phenylacetylene in the presence of this catalyst.

Dialkylation of 2,3-butanedione diketal with 1,8-bis(trimethylsilyl)-2,6-octadiene (BISTRO). Application to the synthesis of estrone derivatives

Abstract Titanium tetrachloride mediated-dialkylation of 2,3-butanedione ketal 2 by 1,8-bis(trimethylsilyl)-2,6-octadiene (BISTRO) 1 led to 1-acetyl-1-methyl-2,5-divinylcyclopentane 4 . This latter was methoxycarbonylated (NaH/dimethylcarbonate) and then alkylated with iodobenzocyclobutene (Cs 2 CO 3 /acetone) to give a benzocyclobutenic intermediate 6 , whose thermolysis provided the 12-oxo-estrane derivatives 8–11 .

Membrane permeation by multidrug-resistance-modulators and non-modulators: effects of hydrophobicity and electric charge.

This study was designed to test the hypothesis that lipophilic cationic drugs with only roughly similar structures mediate the reversal of multidrug‐resistance (MDR) by interacting with membrane phospholipids. The permeation properties of MDR‐modulators and non‐modulators were studied by quantifying their ability to induce the leakage of Sulphan blue through the membrane of negatively charged unilamellar liposomes.