The nucleophilicity of arenethiols can be augmented via hydrogen bonding with "naked" halide anion. The activity of the halide anions follow the order F(-) >> Cl(-) approximately Br(-) approximately I(-) and is dependent on the countercation (Bu(4)N approximately Cs approximately K > Na >> Li). The solvent plays an important role in nucleophilic activation as well as regeneration of the effecti...

poly (vinylpyrrolidone)-grafted silica as an organic-inorganic hybrid material was used as an effective heterogeneous polymeric cosolvent catalyst in organic reactions. this modified silica catalyzed nucleophilic displacement of alkyl halides for easy preparation of alkyl thiocyanates, alkyl cyanides, alkyl azides and alkyl aryl ethers. furthermore, the catalyst was applied for the conversion o...

An efficient and chemoselective cleavage of silyl ethers (primary, secondary and aromatic) by using catalytic quantities of trimethylsilyl bromide (TMSBr) in methanol is reported. A wide range of alkyl silyl ethers such as TBS, TIPS, and TBDPS can be chemoselectively cleaved in high yield in the presence of aryl silyl ethers. The deprotection of silyl esters was also achieved employing catalyti...

a new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) thieno [2,3-d] pyrimidine under refluxing condition with acetic anhydride followed by air...

Mukaiyama Michael addition of silyl enol ethers 13 to the 1,2-quinone-4-carboxylate 6 (formed in situ by oxidation of the catechol ester 8) afforded the 2-subsituted 7-hydroxybenzofuran-4-carboxylates 14 in fair to good yields. Alkyl and aryl systems work well, but highly electron-rich silyl enol ethers could not be used because of competing oxidation.

A new method for the preparation of alkyl aryl sulfides through direct oxidative thiolation of alkanes or ethers with arylsulfonyl hydrazides using di-tert-butyl peroxide (DTBP) as an oxidant catalyzed by Pd(OAc)2 has been reported. The C-H bonds in various alkanes or ethers were successfully converted into C-S bonds to yield the corresponding sulfides in moderate to good yields.

A method for the cleavage of aryl alkyl ethers is presented, involving hot pressurized water and catalytic mineral acid. The protocol applicable on a variety (biorenewable) substrates, not requiring mass-intensive work-up.

Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90 min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has...

Selective hydrogenolysis of the aromatic carbon-oxygen (C-O) bonds in aryl ethers is an unsolved synthetic problem important for the generation of fuels and chemical feedstocks from biomass and for the liquefaction of coal. Currently, the hydrogenolysis of aromatic C-O bonds requires heterogeneous catalysts that operate at high temperature and pressure and lead to a mixture of products from com...

A new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) thieno [2,3-d] pyrimidine under refluxing condition with acetic anhydride followed by air...