Radhika D. Wakharkar

SIMPLE AND PRACTICAL HALOGENATION OF ARENES, ALKENES AND ALKYNES WITH HYDROHALIC ACID/H2O2 (OR TBHP)

Abstract A simple protocol for the halogenation of arenes utilizing a combination of aqueous hydrogen peroxide (34 %) or tert-butylhydroperoxide (70 %) and hydrohalic acid is presented. A similar procedure of oxyhalogenation involving the in situ generation of positive halogen reagents is applied for the preparation of vicinal trans-dibromoalkanes and dichloroalkanes from alkenes. The reaction of alkenes with a combination of hydrochloric acid and hydrobromic acid with hydrogen peroxide gave a mixture of 1-bromo 2-chloro alkanes and 1,2-dibromoalkanes. Oxidative bromination of alkynes is also reported under similar conditions.

SIMPLE AND EFFICIENT CHLORINATION AND BROMINATION OF AROMATIC COMPOUNDS WITH AQUEOUS TBHP (OR H2O2) AND A HYDROHALIC ACID

A combination of aqueous tert-butylhydroperoxide (70%) or hydrogen peroxide (34%) and a hydrohalic acid was found effective in chlorination and bromination of aromatic compounds.

Facile regeneration of carbonyl compounds from oximes and tosylhydrazones with TBHP

Abstract 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

EPZ-10 catalyzed regioselective transformation of alkenes into β-iodo ethers, iodohydrins and 2-iodomethyl-2,3-dihydrobenzofurans

An efficient method for the regioselective synthesis of β-iodo ethers and iodohydrines from styrene, indene and dihydronaphthalene in presence of EPZ-10R has been presented wherein only 0.5 equivalent iodine (I2) has been used. Similarly, o-allylphenols are converted to 2-iodomethyl-2,3-dihydrobenzofurans in high yields. This demonstrates a clean green chemical transformation with significant atom economy.

Studies on bromination of active methylene by a mixture of hydrobromic acid and hydrogen peroxide (or TBHP)

Abstract Studies on bromination of active methylene with a mixture of hydrogen peroxide or tert-butylhydroperoxide (TBHP) and hydrobromic acid are discussed. Substituted acetophenones, benzocyclic ketones provide α-bromo-keto compounds in high yields under this reaction condition.

A convenient oxidative demasking of 1,3-dithiolanes and dithianes to carbonyl compounds with TBHP

Abstract Regeneration of carbonyl compounds from their 1,3-dithiolanes and dithianes was achieved using tert-butyl hydroperoxide (TBHP, aq. 70%) in high yields. Thus, an efficient, economical and experimentally simple protocol for dethioacetalization has been demonstrated.

MICROWAVE ACCELERATED TETRAHYDROPYRANYLATION AND DETETRAHYDROPYRANYLATION OF ALCOHOLS, PHENOLS, AND THIOLS CATALYZED BY HYDRATED ZIRCONIA

ABSTRACT A solvent free and expeditious method for tetrahydropyranylation and detetrahydropyranylation of alcohols, phenols and thiols is described using hydrated zirconia and 3,4-dihydro-2H-pyran (DHP). A comparison of this microwave-accelerated reaction with conventional heating condition is also presented.

Natural Kaolinitic Clay and EPZG R : Efficient Solid Catalysts for Selective Regeneration of Carboxylic Acids from Their Corresponding Allyl or Cinnamyl Esters.

Abstract Natural kaolinitic clay and EPZGR were found to be efficient catalysts for selective regeneration of carboxylic acids from their corresponding allyl or cinnamyl esters. R: Registered trade mark of Contract Chemicals, England.

Wittig–Horner Approach for the Synthesis of Tamoxifen

Abstract A stereoselective synthesis of Z‐tamoxifen, a tetra‐substituted alkene with antiestrogenic activity, is described. The Wittig–Horner reaction has been employed as the key step to establish the olefin stereochemistry.