CsF–Al<SUB>2</SUB>O<SUB>3</SUB> mediated rapid condensation of phenols with aryl halides: comparative study of conventional heating vs. microwave irradiation

Biaryl ethers and thio ethers are formed in high yields by the condensation of phenols and thiophenols with electron-deficient aryl halides using CsF supported on Al2O3 under microwave irradiation in solvent-free conditions

Metal triflates catalyzed efficient synthesis of 3,4-dihydro-2H-1-benzopyrans

Ytterbium triflate efficiently catalyzes an unusual cyclization of o-hydroxybenzaldehydes with 2,3-dihydrofuran and 3,4-dihydro-2H-pyran in the presence of trimethyl orthoformate at ambient temperature to afford a new class of compounds, furo- and pyrano[2,3-b]benzopyrans in excellent yields with high diastereoselectivity. Also, o-hydroxybenzaldehydes reacted smoothly with acetophenones in the presence of a catalytic amount of scandium triflate under similar reaction conditions to give the corresponding 2,4-dialkoxy-2-aryl-3,4-dihydro-2H-1-benzopyrans in high yields

Indium-mediated efficient conversion of azides to carbamates

A novel and efficient method for the high yield preparation of carbamates by the reaction of azides with several chloroformates using indium metal in DMF at ambient temperature is described for the first time

Dy(OTf)<SUB>3</SUB>-immobilized in ionic liquids: a novel and recyclable reaction media for the synthesis of 2,3-unsaturated glycopyranosides

D-Glycals react smoothly with a variety of alcohols, phenols and hydroxy α-amino acids in the presence of 5 mol% dysprosium triflate immobilized in 1-butyl-3-methylimidazolium hexafluorophosphate under mild reaction conditions to afford the corresponding 2,3-unsaturated glycopyranosides in excellent yields with high α-selectivity. The catalyst immobilized in ionic liquids was recycled in subsequent reactions without any apparent loss of activity

Highly stereoselective synthesis of 2,3- unsaturated thioglycopyranosides employing molecular iodine

Molecular iodine has been utilized for the first time for the thioglycosidation of D-glycals with various thiols to afford the corresponding 2,3-unsaturated thioglycosides in high yields. In the case of tri-O-acetyl-D-glucal, the α-anomer was obtained exclusively. The use of readily available iodine makes this method quite simple, more convenient, and practical

Lithium perchlorate catalyzed regioselective ring opening of aziridines with sodium azide and sodium cyanide

Aziridines react smoothly with sodium azide and sodium cyanide in the presence of catalytic amount of lithium perchlorate under essentially mild and neutral reaction conditions to afford the corresponding β-azido and β-cyanoamines in high yields with high regioselectivity

Montmorillonite clay-catalyzed stereoselective syntheses of aryl-substituted (E)- and (Z)-allyl iodides and bromides

An efficient and rapid procedure for the synthesis of allyl iodides and bromides from Baylis-Hillman adducts using clay-supported sodium iodide and sodium bromide is described. Improved yields and enhanced rates have been achieved by employing microwave irradiation

LiBF<SUB>4</SUB>-mediated C-glycosylation of glycals with allyltrimethylsilane: a facile synthesis of allyl C-glycosylic compounds

The treatment of glycals with allyltrimethylsilane in the presence of lithium tetrafluoroborate in acetonitrile gave the corresponding allyl 2,3-unsaturated C-glycosylic compounds in excellent yields with high anomeric selectivity

Iron (III) chloride as mild and efficient reagent for the α-thiocyanation of ketones: an expedient synthesis of α-oxo thiocyanates

A simple and efficient method for the α-thiocyanation of ketones has been developed; anhydrous iron(III) chloride is used under mild conditions to produce α-oxo thiocyanates in good to high yields and with high selectivity. The use of inexpensive and readily available iron(III) chloride makes this procedure simple, convenient, and practical