Expedited Route to Fully Substituted Amino-Pyrazole Building Blocks and Their Further Transformations

Abstract

We report here an efficient and easily reproducible two-step approach to heterocycle-substituted amino-pyrazoles from heterocyclic acetonitriles and their unprecedented subsequent transformations to fully substituted pyrazoles. Such transformations include regioselective derivatization from polyamino derivatives, formation of tetracyclic compounds in up to 45% overall yield, and deaminative transformations through diazotization, followed by arylation through Suzuki–Miyaura cross-coupling and C–H activation, providing arylated pyrazoles in up to 71% yield over four steps. This strategy allows the swift introduction of significant molecular complexity to a range of scaffolds.

2-Azahetaryl-2-(oxoindolin-2-ylidene)acetonitriles as Colorimetric Probes for Zn: Synthesis and Optical Properties

“…All chemicals and solvents were analytical grade and used without further purification. Isatin 2a , 5-methylisatin 2b , and 5-methoxyisatin 2c were provided by Enamine Ltd. 2-(Benzo­[ d ]­thiazol-2-yl)­acetonitrile 1a was synthesized by a known method . 2-(Benzo­[ d ]­thiazol-2-yl)­acetonitrile 1b was synthesized as described in Section .…”

4-(Benzo[d]thiazol-2-yl)-1-(2-nitrophenyl)-1H-1,2,3-triazol-5-amine

“…Progress of reactions and purity of the synthesized compounds were examined by means of TLC on Silufol UV-254 plates, and visualization was performed using UV lamp (254 nm). 2-Nitrophenyl azide 1 [25] and 2-(benzo[d]thiazol-2-yl)acetonitrile 2 [26] were synthesized according to the literature procedures.…”