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The in situ generated [TpMe2Ir(C6H5) 2] fragment induces both aromatic and aliphatic C-H bond activation reactions, along with C-C bond formation, when heated with benzene and 1,2-dimethoxyethane.

An advantageous methodology for the oxidative debenzylation of ethers has been developed. Very low amounts of a catalyst system based on vanadyl acetylacetonate and a triazole type pincer ligand allow the selective oxidative cleavage of a number of O-benzyl ethers in the presence of oxygen as the sole oxidant. The methodology tolerates a number of functional groups such as halo-, alkoxy-, or trifluoromethylarenes, alkyne, alkene, ether, and acetal units. Large-scale deprotections can be also carried out by the optimized procedure, which is amenable to enantioenriched reactants as well. (Figure presented.).

New chiral Jacobsen's catalysts grafted onto alkoxyl-modified ZPS-PVPA are synthesized and applied in asymmetric epoxidations of unfunctionalized olefins. Specially, the supported catalysts indicate excellent catalytic activities (conv%, up to 96; sele%, up to 96; ee%, up to >99) in the absence of N-methylmorpholine N-oxide (NMO) by virtue of the special configurations of the catalysts. The superior stability (recycling for ten times) and the comfortable dispositions in large-scale reactions (such as 200 times) grant the potential application in industry to the heterogeneous catalysts.

A microwave-irradiated alcohol-protecting strategy based on gold catalysis utilizing benzyl alcohol, tert-butyl alcohol and triphenylmethanol as alkylating reagents has been developed. This protecting strategy has wide functional group tolerance with satisfactory yields for the majority of the selected alcohols. The mechanism of this transformation was probed with oxygen-18 isotope labelled alcohols assisted by GC-MS techniques and chemical kinetic experiments. This strategy provides an efficient, straightforward and alternative approach to the preparation of benzyl, tert-butyl and trityl ethers in organic synthesis.

The present invention provides novel phenylcycloalkylmethylamme derivatives, and methods of preparing phenylcycloalkylmethylamme derivatives. The present invention also provides methods of using phenylcycloalkylmethylamme derivatives and compositions of phenylcycloalkylmethylamme derivatives. The pharmaceutical compositions of the compounds of the present invention can be used for treating and/or preventing obesity and obesity related co- morbid indications and depression and depression related co-morbid indications.

Mixed acetals and organotrifluoroborates undergo BF3· OEt2-promoted cross-couplings to give dialkyl ethers under simple, mild conditions. A survey of reaction partners identified a hydroxamate leaving group that improves the regioselectivity and product yield in the BF 3·OEt2-promoted coupling reaction of mixed acetals and potassium alkynyl-, alkenyl-, aryl- and heteroaryltrifluoroborates to access substituted dialkyl ethers. This leaving group enables the reaction to proceed rapidly under mild conditions (0 °C, 5-60 min) and permits reactions with electron-deficient potassium aryltrifluoroborates that are less reactive with other acetal substrates. A study of the reaction mechanism and characterization of key intermediates by NMR spectroscopy and X-ray crystallography identified a role for the hydroxamate moiety as a reversible leaving group that serves to stabilize the key oxocarbenium intermediate and the need for a slight excess of organodifluoroborane to serve as a catalyst. A secondary role for the boron nucleophile as an activating ligand was also considered. These studies provide the basis for a general class of reagents that lead to dialkyl ethers by a simple, predictable cross-coupling reaction.

Naphthalene-catalysed reductions of PhCH(OR)2 (R = Me, CH2CH2OMe) acetals by lithium metal, followed by reactions with electrophiles (H+, TMSCl, nBuBr, CH2=CHCH2Br), proceed with high chemoselectivity when the reductions are carried out at -90 °C especially for R = CH2CH2OMe. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany 2002.

The first catalytic system employing triorganothallium compounds in the formation of carbon-carbon bonds, is described.

Titanium tetrachloride rapidly anomerizes methyl 2,3,4,6-tetra-O-benzyl-β-D-glucopyranoside in dichloromethane at 25 deg C.Evidence for the proposal that the benzyloxymethyl group on C-5 and the ring oxygen of the glucoside cooperate to prompt the reaction is described.The reagent anomerizes the interglycosidic linkage of several disaccharide derivatives.

The etherifications listed in tables 1 and 2 are achieved by converting hydroxy-derivatives, which contain additional oxygen functions, into thallium(I) alkoxides with thallium ethoxide, and treatment with haloalkanes.The scope and limitations of the method are discussed.