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Simple chiral aziridino alcohols 2-5, easily available from L-serine, L-threonine or L-allo-threonine, have been used as ligands to promote the addition of Et(2)Zn to the diphenylphosphinoylimine 1 (Ar=Ph). Enantioselectivities of up to 94% could be obta
N/A / Link / Andersson , PG / 1996

Combination of variable temperature NMR and CD spectroscopy, and molecular mechanics computations shows that dihydroquinidine exists in two conformations, anti,open (80-90%) and syn,closed (10-20%) separated by a barrier of 8.3 kcal/mol in ether solution
N/A / Link / BERG , U / 1995

The acid-catalysed solvolysis of 9(2-phenoxy-2-propyl)fluorene in mixtures of water with acetonitrile or methanol at 25 degrees C provides 9-(2-hydroxy-2-propyl)fluorene, 9-(2-propenyl)fluorene, and 9-(2-acetamido-2-propyl)fluorene or 9-(2-methoxy-2-prop
N/A / Link / SIDHU , H / 1994

Uppsala universitet Övrigt
N/A / Link / Hedberg , O / 1996

The intramolecular OH stretching frequency shift observed for water on formation of 'cation-water...H-bond acceptor' complexes is highly non additive. The uncoupled OH frequency shift has been calculated by ab initio methods for q(+)-OH2 and OH2...q(-) c
N/A / Link / HERMANSSON , K / 1995

Ketones, labelled with C-11 in the carbonyl position, were synthesised by the use of [C-11]carbon monoxide in palladium-promoted carbonylative coupling reactions of organic halides with organotin reagents, 100-300 MBq of compounds 1-3 were obtained withi
N/A / Link / ANDERSSON , Y / 1995

A 1,2-dicarba-closo-dodecaborane(12) derivative, containing a hydrophilic diol group and an amino group 2-[2-(3-aminopropyl)-1,2-dicarba-closo-dodecaboran(12)-l-ylmethoxy]-1,3-propanediol (1a), has been synthesised from the dibenzyl ether of 2-[1,2-dicar
N/A / Link / MALMQUIST , J / 1994

The heteropolyacid H-5[PMo10V2O40] is an effective oxygen-activating catalyst in palladium-catalyzed aerobic allylic acetoxylation of cyclohexene.
N/A / Link / Grennberg , H / 1996

We have performed ab-initio calculations on 1:1 complexes of triglyme (triethylene glycol dimethyl ether) with different meter ions. Several stable tetradentate complexes have been found for each cation. The energy difference between the least stable and
N/A / Link / Johansson , P / 1996

N/A / Link / Bergson , G / 1996

The adsorption of human serum proteins to mono-, di- and tri-cyanocarbon ligands was studied in the presence of the water-structuring salt Na2SO4. All of the ligands adsorbed proteins to varying degrees when coupled to agarose via a divinylsulfone-derive
N/A / Link / Berna , PP / 1996

The preparation of the unnatural bicyclic alpha-amino acids 7 and 8 is described along with their utility as chiral ligands in the copper-catalyzed enantioselective allylic oxidation of cylohexene with tert-butyl perbenzoate. These bicyclic amino acids w
N/A / Link / Sodergren , MJ / 1996

A model for subsequent use in molecular dynamics simulation of the V2O5 gel host is derived by reproducing the observed crystal structure. The band-like gel structure is then mimicked through a strategy whereby space is introduced between the layers of c
N/A / Link / Linde , J / 1996

The syntheses of two novel para-carboranyl and two novel nido-carboranyl phenanthridinium compounds as potential boron delivery agents for Neutron Capture Therapy are described. Copyright (C) 1996 Elsevier Science Ltd
N/A / Link / Tjarks , W / 1996

The total electron density of a water molecule differs significantly from the superposition of the O + H + H spherical-atom densities by way of bonding and lone-pair electron charge accumulations. Such non-spherical electron density features on neighbour
N/A / Link / Hermansson , K / 1996

Oxidation of 5-unsaturated 3 beta-hydroxy steroids 1 to the corresponding 4-en-3-one derivatives 2 can be performed efficiently by acetone at reflux in the presence of a catalytic system consisting of either (PPh(3))(3)RuCl2 (3) and K2CO3 or [(C(4)Ph(4)C
N/A / Link / Almeida , MLS / 1996

The mechanism of the palladium-catalyzed elimination of acetic acid from allylic acetates has been studied. It was found that this process can take place not only via conventional syn elimination of palladium hydride but also via an anti elimination. pat
N/A / Link / ANDERSSON , PG / 1995

An updated version of the CPSR software package for powder pattern fitting and structure refinement offers major advantages over previous versions. An optional use of the new figure-of-merit function, that takes into account a systematic behaviour of res
N/A / Link / ANDREEV , YG / 1995

Crystals of LuB4, LuAlB4, and Lu2AlB6 were grown by the high-temperature aluminium solution method using lutetium oxide and crystalline boron powders as starting materials. The growth conditions for obtaining single crystals of relatively large size were
N/A / Link / Okada , S / 1996

We herein describe a novel example of a palladium-catalysed asymmetric allylic elimination leading to enantiomerically enriched dienes. The use of chiral ligands such as BINAP or DIOP allows the catalyst to discriminate between the enantiotopic hydrogens
N/A / Link / Koroleva , EB / 1996

(eta(3)-Allyl)palladium complexes possessing various allylic beta-substituents (X = Cl, OCH3, H) and ancillary ligands on palladium (L = Cl-, F-, PH3) have been studied at the second-order Moller-Plesset (MP2) and fourth-order Moller-Plesset (MP4) pertur
N/A / Link / Szabo , KJ / 1996

A large incoming group C-11/C-14 kinetic isotope effect of 1.0104 +/- 0.0023 has been measured for the S(N)2 reaction between benzyl chloride and labeled cyanide ion in 20% aqueous DMSO at 30.00 degrees C. These large incoming group kinetic isotope effec
N/A / Link / Matsson , O / 1996

The crystal chemistry of the B4C-type structures is described. New structural data for B12S, B13Se and B6O are presented. It is found that B6O with a microhardness larger than that of B4C invariably contains a high concentration of vacancies at the oxyge
N/A / Link / Lundstrom , T / 1996

The palladium-catalyzed intramolecular 1,4-oxidation of conjugated dienes has been extended to carbon-carbon bond formation. Two different methods were developed. In the first method, a vinylpalladium intermediate is generated in the side chain which add
N/A / Link / Backvall , JE / 1996

Palladium-catalyzed 1,4-oxidation of conjugated dienes involving carbon-carbon bond formation has been realized The reaction is performed with both acyclic and cyclic dienes with a carbon chain containing a terminal or internal triple bond. A vinylpallad
N/A / Link / Nilsson , YIM / 1996