Highly active water-soluble palladium catalyst for the regioselective carbonylation of vinyl aromatics to 2-arylpropionic acids

This is the published version. Copyright © The Royal Society of Chemistry 2000A novel water-soluble Pd complex containing pyridine carboxylate and TPPTS as ligands is a highly active catalyst for the carbonylation of vinyl aromatics under biphasic conditions and provides high regioselectivity to 2-arylpropionic acids

Highly active supported palladium catalyst for the regioselective synthesis of 2-arylpropionic acids by carbonylation

This is the published version. Copyright © Royal Society of Chemistry 1999A catalyst system consisting of supported palladium in the presence of phosphine ligands, TsOH and LiCl catalyses the carbonylation of 1-arylethanols to 2-arylpropionic acids with significantly improved activity and regioselectivity; the catalyst can be recycled with no loss in activity and selecivity

Counterion effects in iminium-activated electrophilic aromatic substitutions of pyrroles.

Electrophilic substitution of pyrroles by a,b-unsaturated iminium ions is slow in acetonitrile when only weakly basic counterions are present. When the reactions are carried out in the presence of KCF3CO2, fast deprotonation of the intermediate r-adducts occurs, and the rate constant for the rate-determining CC bond-forming step can be predicted from the electrophilicity parameter E of the iminium ion and the N and s parameters of the pyrroles

Kinetics and mechanism of organocatalytic aza-Michael additions: direct observation of enamine intermediates.

The imidazoles 1a–g add to the CC-double bond of the iminium ion 2 with rate constants as predicted by the equation log k = sN(N + E). Unfavourable proton shifts from the imidazolium unit to the enamine fragment in the adduct 3 account for the failure of imidazoles to take part in iminium-activated aza-Michael additions to enals

2-Hydr­oxy-16-[(E)-4-hydr­oxy-3-methoxy­benzyl­idene]-13-(4-hydr­oxy-3-methoxy­phen­yl)-11-methyl-1,11-diaza­penta­cyclo­[12.3.1.02,10.03,8.010,14]octa­deca-3(8),4,6-triene-9,15-dione

In the title compound, C32H30N2O7, the piperidone ring adopts a chair conformation and the five-membered ring of the dihydro­indenone ring system adopts an envelope conformation. Intra­molecular O—H⋯N and C—H⋯O hydrogen bonds occur. The dihedral angle between the two hydr­oxy-subsituted methoxy­phenyl rings is 71.12 (5)°. In the crystal structure, mol­ecules are connected by inter­molecular O—H⋯O hydrogen bonds, forming layers parallel to (001). These layers are further connected by C—H⋯O hydrogen bonds, forming a three-dimensional network

Asymmetric organocatalysis of the addition of acetone to 2-nitrostyrene using N-diphenylphosphinyl-1,2-diphenylethane-1,2-diamine (PODPEN)

The highly enantioselective addition of acetone to 2-nitrostyrene, using N–diphenylphosphinyl-trans-1,2-diphenylethane-1,2-diamine (PODPEN) as catalyst, is described

Indole and azaindole halogenation catalyzed by the RebH enzyme variant 3-LSR utilizing co-purified E. coli reductase

Biocatalytic C-H halogenation is becoming increasingly attractive due to excellent catalyst-controlled selectivity and environmentally benign reaction conditions. Significant efforts have been made on enzymatic halogenation of industrial arenes in a cost-effective manner. Here we report an unprecedented enzymatic halogenation of a panel of industrially important indole, azaindole and anthranilamide derivatives using a thermostable RebH variant without addition of any external flavin reductase enzyme. The reactions were catalyzed by the RebH variant 3-LSR enzyme with the help of a co-purified E. coli reductase identified as alkyl hydroperoxide reductase F (AhpF)

Hydrogen storage in metal-organic and covalent-organic frameworks by spillover

Covalent-organic framework COF-1 and metal-organic frameworks HKUST-1 and MIL-101 were synthesized and studied for hydrogen storage at 77 and 298 K. Although MIL-101 had the largest surface area and pore volume among the three materials, HKUST-1 had the highest uptake (2.28 wt %) at 77 K. However, the H 2 storage capacity at 298 K and high pressure correlated with the surface area and pore volume. The H 2 storage in the COF and MOF materials assisted by hydrogen spillover, measured at 298 K up to a pressure of 10 MPa, have been examined for correlations with their structural and surface features for the first time. By using our simple technique to build carbon bridges, the hydrogen uptakes at 298 K were enhanced significantly by a factor of 2.6–3.2. The net uptake by spillover was correlated to the heat of adsorption through the Langmuir constant. Results on water vapor adsorption at 298 K indicated that COF-1 was unstable in moist air, while HKUST-1 and MIL-101 were stable. The results suggested that MIL-101 could be a promising material for hydrogen storage because of its high heat of adsorption for spiltover hydrogen, large surface area and pore volume, and stability upon H 2 O adsorption. © 2007 American Institute of Chemical Engineers AIChE J, 2008Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57505/1/11362_ftp.pd

A highly enantioselective alkene methoxycarbonylation enables a concise synthesis of (S)-flurbiprofen

The authors thank the EPSRC for funding for this programme from EP/MC038868/1 and via the DTG.A highly enantioselective synthesis of (S)-Flurbiprofen methyl ester in two steps from commercially available 4-bromo-2-fluoro-1,1'-biphenyl is shown. [PdCl2((S)-Xylyl-Phanephos)] catalyst is used to accomplish both Grignard cross-coupling and the highly enantioselective intermolecular methoxycarbonylation reaction.PostprintPeer reviewe