Only few efficient methods for the preparation of polyazoles containing three or four nitrogen atoms in each azole cycle exist. We have developed a novel synthetic strategy that allows sequential assembly 1,2,3-triazole, 1,2,4-triazole, and tetrazole fragments into new stable polyazole. Along strategy, some known procedures been optimized to achieve better conversion, selectivity, and, general,...

Addition of water to the product formed when LaCl3 and 1H-5-(2-pyridyl)tetrazole (LH) were treated with an excess of triethylamine in ethanol, resulted in the reversible formation of a hydrogel, which when further treated with EtOH-iPrOH produced crystals of [LaL3(H2O)3].(H2O)4, as determined by X-ray crystallography.

A diastereo- and enantioselective aldol reaction between aldehydes and a synthetically useful ketomalonate 1c as a hydrated form was developed, and either anti- or syn-aldol adducts having a chiral tetrasubstituted carbon center were obtained in high enantioselectivities by use of a tetrazole analogue of L-proline (S)-2 or an axially chiral amino sulfonamide (S)-3 as catalyst.

A novel coordination nanocage was obtained with in situ-generated tetrazole ligands from the cobalt-thiacalix[4]arene system. Four in situ-generated 1,3-bis(2H-tetrazol-5-yl)benzene ligands bolster eight Co4-calix shuttle-cock-like secondary building units (SBUs) into a hollow tetragonal prism with a high surface area. The unprecedented {Co32} nanocage presents the highest nuclearity example.

Ammonia in the tetrazole Ugi variation together with α-amino acid methyl ester-derived isocyanides provides tetrazolopiperidinones in good to high yields in one pot. The scope and limitations of this reaction were investigated by performing >70 reactions. The scaffold is useful to fill high-throughput screening decks and in structure-based drug design.

A catalytic route for enantioselective total synthesis of cell adhesion inhibitor BIRT-377 is described. The quaternary stereocenter was constructed through l-proline-derived, tetrazole-catalyzed direct asymmetric alpha-amination of 3-(4-bromophenyl)-2-methylpropanal with dibenzyl azodicarboxylate. In the course of these studies, a one-pot trifluoro acetylation/selective benzyloxycarbonyl depro...

Rh(III)-catalyzed direct olefination reaction via aromatic C-H bond activation is described using tetrazole as the directing group. This reaction provides a straightforward way for the synthesis of ortho-alkenyl aryl tetrazoles. Various functional groups tolerate the reaction conditions and afford the corresponding products in moderate to excellent yields.

A novel (3,4)-connected 3D self-penetrating metal-organic framework with a nanometre-scale cavity constructed from metallacalix[4]arene building blocks and Keggin-type polyanions has been obtained by using a 1,3-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)propane ligand.