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The nuclear as well as side-chain bromination of activated aromatic substrates has been achieved in high yields and substantial regioselectivity with N-Bromosuccinimide (NBS) over HZSM-5.

A mild and effective procedure for directly converting secondary, tertiary and benzylic alcohols into the corresponding iodides is described using I2 in refluxing petroleum ether. The reaction proceeds with inversion of configuration.

Catalytic version of the H2O2–TS–1 combination has been shown to display a good reaction selectivity in the liquid-phase oxidation of anilines to symmetrical azoxybenzenes.

Catalytic system of TS-1-H 2 O 2 combination has been shown to display remarkable reaction selectivity in the liquid-phase oxidative cleavage of oximes to carbonyl compounds in excellent yields.

A chromium-containing medium-pore molecular sieve (Si:Cr > 140:1) having MEL (CrS-2) topology efficiently catalyses the direct oxidation of various primary amines to the corresponding nitro compounds using 70%tert-butyl hydroperoxide (TBHP) as the oxidant.

Catalytic system of TS-1 - H2O2 combination has been shown to display remarkable reaction selectivity in the oxidation of benzylic and allylic amines to oximes in excellent yields.

Ultrasound irradiation has resulted in the selective monobromination of activated aromatics with N-Bromosuccinimide (NBS) in carbon tetrachloride at ambient conditions in the absence of any added catalyst.

Chromium-containing medium-pore molecular sieve (Si/Cr > 140) having MEL (CrS-2) topology efficiently catalyses the chemoselective epoxidation of various olefins to the corresponding epoxides using 70%tert-butyl hydroperoxide (TBHP) as an oxidant.

Titanium Silicates (TS-1 and TS-2) catalyzed efficiently the selective oxidation of both linear and cyclic ethers into the corresponding acids and lactones respectively, using dil. H 2 O 2 as the oxidant.

Chromium containing medium pore molecular sieve ( Si Cr > 140 ) having MEL (CrS-2) topology selectively catalyzes the oxidation of various benzylic alcohols to the corresponding carbonyl compounds using 70% tert - butyl hydroperoxide (TBHP) as an oxidant.

Chlorobenzotrifluorides ( 2 3 ), under typical Friedel - Crafts reaction conditions, react efficiently with aromatic compounds (1) to afford 1,1-dichlorodiphenylmethanes, (4) in excellent yield and purity.

70% tert-Butyl hydroperoxide (TBHP) has been found to be an efficient and selective reagent for the mild oxidative cleavage of the CN of oximes and tosylhydrazones to yield their corresponding carbonyl compounds

Natural kaolinitic clay possessing transition metals such as Fe and Ti in its lattice has been found to catalyze efficiently the chemoselective acetalization and thioacetalization of variety of carbonyl compounds with ethane-1,2-diol and ethane-1,2-dithiolrespectively.

Natural kaolinitic clay possessing transition metals such as Fe, Ti in its lattice has been found to catalyze efficiently the protection of a variety of alcohols with 2,3-dihydro-4H-pyran (DHP) and hexamethyldisilazane (HMDS) at ambient conditions.

Two new polymeric cinchona alkaloid derived ligands were synthesized and utilized in the asymmetric dihydroxylation of olefins, exhibiting high enantioselectivities in the case of aliphatic terminal olefins under heterogeneous phase. © 1997 Elsevier Science Ltd.

A mild and efficient catalytic method for benzylic oxidation of alkylarenes to the corresponding carbonyl compounds in good yields is described using a catalytic amount of reusable solid, mesoporous chromosilicate (Cr-MCM-41) and 70% tert-butyl hydroperoxide (TBHP) as oxidant.

A catalytic asymmetric synthesis of ethyl (2R,3S)-N-(p-toluenesulfonyl)-3-amino-4-cyclohexyl-2-hydroxybutyrate 7 in 96% ee from cheaply available cyclohexanone is described employing Sharpless asymmetric aminohydroxylation as the key step.

Transesterification and transthiolesterification of β-keto esters with variety of alcohols and thiols and selective protection of carbonyl functions with various protecting groups catalyzed by natural kaolinitic clay are described. The clay has been found to be an efficient catalyst in transesterifying long chain alcohols, unsaturated alcohols, and phenols to give their corresponding β-keto esters in high yields. For the first time, transthiolesterification of β-keto esters with a variety of thiols has been achieved under catalytic conditions. Clay also catalyzes selective transesterification of β-keto esters by primary alcohols in the presence of secondary and tertiary alcohols giving corresponding β-keto esters. A systematic study involving the reactivity of different nucleophiles (alcohols, amines, and thiols) toward β-keto esters is also described. Sterically hindered carbonyl groups as well as α,β-unsaturated carbonyl groups underwent protection without the deconjugation of the double bond. Chemosele...

Kaolinitic clay efficiently catalyses the reaction of sulfur monochloride with arenes to yield symmetrical 4,4′ arene disulfides in a single step under heterogeneous phase.

Osmium tetroxide catalyzed asymmetric aminohydroxylation of silyl enol ethers using cinchona alkaloids as chiral ligands and chloramine-T as the nitrogen source affords enantiomerically pure α-amino ketones.

A mild and efficient catalytic method for the benzylic oxidation of alkyl arenes to the corresponding tert. butyl aryl peroxides is described using a catalytic amount of reusable solid, RuIII-exchanged Montmorillonite K10 and 70% tert. butyl hydroperoxide (TBHP) as oxidant.