the solvent free route for the synthesis of diaryl sulfoxides from arenes and thionyl chloride in the presence of lewis acids such as aluminum chloride and ferric chloride on silica gel are described.

Friedel-Crafts alkylation of aromatic systems is a classic reaction in organic chemistry, for which regiospecific mono-alkylation, however, is generally difficult to achieve. In nature, methyltransferases catalyze the addition of methyl groups to a wide range of biomolecules thereby modulating the physico-chemical properties of these compounds. Specifically, S-adenosyl-L-methionine dependent C-...

The reaction of indole with chalcones, to give Michael-type adducts, was found to occur with good efficiency (up to 98% yield) and moderate enantioselectivity (up to 52% e.e.) in the presence of a chiral BINOL-based phosphoric acid. Furthermore, the alkylation products can be obtained in much higher e.e.s after one only crystallization.

The most widely known electrophilic agents are protic acids and compounds with an electronsextet partial structure. Recent research has aimed at the development of new electrophilic reagents, with greater reactivity on the one hand and higher selectivity on the other, which would largely obviate the addition of Lewis acids (Friedel-Crafts catalysts), and also alIow control of the isomer ratio i...

The concise and efficient total synthesis of (+)-bionectins A and C is described. Our approach to these natural products features a new and scalable method for erythro-β-hydroxytryptophan amino acid synthesis, an intramolecular Friedel-Crafts reaction of a silyl-tethered indole, and a new mercaptan reagent for epipolythiodiketopiperazine (ETP) synthesis that can be unravelled under very mild co...

Introduction In a previous paper [2] we described that Friedel-Crafts phenylation of the ringsystems (NPCl2)3-n(NSOCl)w (n = 1, 2) leads to a reaction at the sulphur atoms. Efforts to substitute a phosphorus-bonded chlorine atom failed however, even in the presence of an excess of A1C13. It has been demonstrated in phosphazene chemistry [3-6] that a PClAm group (Am = amino) is more reactive tow...