Microwave-assisted chemoselective synthesis of novel pyrazolo[3,4-b]thieno[3,4-e]pyridines: substitution induced axial chirality

Synthesis of highly functionalized 2-thiaspiro[4.5]deca-6,8-dienes via atom efficient tandem Michael addition/Thorpe–Ziegler cyclization

“…We instigated the work by synthesizing the precursor 3 from the reaction of dihydrothiophen-3(2H)-one and two equivalents of aromatic aldehydes following our earlier report. 21 Similarly, the 2-(1-arylethylidene)malononitriles 4 were synthesized from the reaction of malononitrile and 1-(aryl)ethan-1-ones following a literature report (Scheme 1). 22 Subsequently, the reaction of 2,4-bis((Z)-2,4-dichloro-benzylidene)dihydrothiophen-3(2H)one 3g and 2-(1-(p-tolyl)ethylidene)malononitrile 4c that With the optimized reaction conditions in hand and the structure of the product 1w established, we then investigated the feasibility of this tandem reaction towards library creation.…”

Iminothioindoxyl Donors with Exceptionally High Cross Section for Protein Vibrational Energy Transfer

“…The authors have cited additional references within the Supporting Information. [34][35][36][37][38][39][40][41][42][43][44][45][46]…”

Cyclisation reaction between 3-methylquinoxaline-2-thione and benzaldehydes into 3-benzyl-2-aryl-thieno[2,3-b]quinoxaline promoted by Brønsted acids

“…First, the thiol function of intermediate A-which is a tautomer of 1-reacts with a molecule of benzaldehyde under acidic conditions to afford intermediate B. Under these acidic conditions, B would be dehydrated to allow the formation of thiol-carbenium C, which could cyclize to give 2-aryl-2,3-dihydrothieno[2,3-b]quinoxaline D. Then, a Knoevenagel-type condensation under acidic conditions of the intermediate D with another molecule of benzaldehyde leads to compound F [19], which is transformed into the desired 2,3-disubstituted thieno[2,3-b]quinoxaline (6) via a rearomatization process.…”