02501nas a2200193 4500008004100000022001400041245009300055210006900148260007100217300001400288490000700302520174800309100002802057700002102085700002502106700002102131700002902152856012602181 2007 eng d a0888-588500aEnvironmentally benign catalytic hydroformylation-oxidation route for naproxen synthesis0 aEnvironmentally benign catalytic hydroformylationoxidation route a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC a8480-84890 v463 a

Hydroformylation of 6-methoxy-2-vinylnaphthalene (MVN), using homogeneous Rh(CO)acac) as a catalyst and a chelating bidentate ligand (1,2-bis-(diphenylphosphino) ethane, dppe), followed by oxidation of the product (2-(6-methoxynaphthyl) propanal, 2-MNP) has been studied as an alternative route for the synthesis Of D,L-naproxen. The feasibility of the MVN hydroformylation route has been demonstrated, and a detailed study has been reported on the key hydroformylation step. The roles of the catalyst, ligands, and solvents, as well as the effect of reaction conditions on the reaction rate and regioselectivity of the product 2-MNP, have been investigated. With Rh(CO)2(acac) as a catalyst and dppe as a ligand, > 98% selectivity to 2-MNP (an important precursor to D,L-naproxen) has been achieved. A possible mechanism to explain the variation in regioselectivity with Rh(CO)(2)(acac) as a catalyst and dppe as a ligand has been discussed. The kinetics of the hydroformylation step has been investigated and a rate equation has been proposed. The second step in the proposed route for naproxen-the oxidation of 2-MNP to 2-(6-methoxynaphthyl) propanoic acid (2-MNPA, or naproxen) - has been studied using Na2WO4 as a catalyst and tetrabutyl ammonium hydrogen sulfate (TBAHS) as the phase-transfer catalyst with H2O2 as the oxidant for the first time. Screening of the catalysts that consisted of the early transition metals, such as salts of tungsten, vanadium, and molybdenum showed that Na2WO4 gives the best performance for the oxidation step with > 80% selectivity to 2-(6-methoxynaphthyl)propanoic acid (2-MNPA/naproxen). This study would be valuable in developing a new environmentally benign route for naproxen synthesis.

1 aRajurkar, Kalpendra, B.1 aTonde, Sunil, S.1 aDidgikar, Mahesh, R.1 aJoshi, Sunil, S.1 aChaudhari, Raghunath, V. uhttps://library.ncl.res.in/content/environmentally-benign-catalytic-hydroformylation-oxidation-route-naproxen-synthesis-001632nas a2200193 4500008004100000022001400041245008400055210006900139260007100208300001400279490000700293520090800300100002501208700001601233700002101249700002101270700002901291856011801320 2010 eng d a0888-588500aImmobilized palladium nanoparticles catalyzed oxidative carbonylation of amines0 aImmobilized palladium nanoparticles catalyzed oxidative carbonyl a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB a1027-10320 v493 a

Catalytic application of immobilized palladium nanoparticles for synthesis or ureas by oxidative carbonylation of amines has been investigated. This is the first report oil oxidative carbonylation of amines to ureas using immobilized palladium nanoparticles catalyst. The palladium nanoparticles were immobilized on a NaY zeolite support through 3-aminopropyl-trimethoxysilane (APTS) as anchoring agent. The [Pd]-APTS-Y catalyst along with NaI promoter showed high conversion and selectivity to the desired urea products over several amine compounds including ail example of an aliphatic amine precursor even at 333 K. The immobilized catalyst was easily separated and recycled several times without any loss of activity. The role of different solvents, iodide promoters, iodide to Pd ratio, concentration of substrates, and temperature on the overall yield of the reaction was also investigated.

1 aDidgikar, Mahesh, R.1 aRoy, Debdut1 aGupte, Sunil, P.1 aJoshi, Sunil, S.1 aChaudhari, Raghunath, V. uhttps://library.ncl.res.in/content/immobilized-palladium-nanoparticles-catalyzed-oxidative-carbonylation-amines-002196nas a2200265 4500008004100000022001400041245009500055210006900150260007300219300001000292490000800302520124600310653001001556653002301566653001801589653000901607653003701616100002501653700002101678700002101699700002601720700002901746700002901775856012601804 2011 eng d a1381-116900aOxidative carbonylation of amine using water-soluble palladium catalysts in biphasic media0 aOxidative carbonylation of amine using watersoluble palladium ca aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJAN a20-280 v3343 a

Application of water-soluble palladium catalysts for oxidative carbonylation of aniline to N,N' diphenyl urea (DPU) has been reported. The water-soluble palladium catalysts prepared from sulfonated N-containing ligands were found to be highly stable under reaction conditions and easily recyclable due to insoluble urea product in the reaction medium. This is in contrast to the sulfonated phosphine ligands, which are vulnerable to oxidation under reaction conditions, showing poor activity and stability. Commercially available as well as laboratory synthesized ligands were used for preparing water-soluble palladium catalysts, for oxidative carbonylation of aniline. The best activity was obtained for Pd complex with disodium 2,2'-bipyridine-4,4'-disulfonate (Bipy-DS) ligand. Under optimized conditions Pd(BipyDS)Pd(OAc)(2) catalyst gave TOF of similar to 210h(-1) with aniline conversion of similar to 97% with similar to 91% selectivity for N.N'-diphenyl urea. It was found that the catalyst was easily reusable up to five times, with negligible loss in the catalytic activity. The effect of reaction parameters was investigated and a plausible reaction mechanism has been proposed. (C) 2010 Elsevier B.V. All rights reserved.

10aAmine10aBiphasic catalysis10aCarbonylation10aUrea10aWater-soluble palladium catalyst1 aDidgikar, Mahesh, R.1 aJoshi, Sunil, S.1 aGupte, Sunil, P.1 aDiwakar, Makarand, M.1 aDeshpande, Raj, Madhukar1 aChaudhari, Raghunath, V. uhttps://library.ncl.res.in/content/oxidative-carbonylation-amine-using-water-soluble-palladium-catalysts-biphasic-media-0