An Efficient Combinatorial Synthesis of Novel Thiazolidinone‐Bis Schiff Base Hybrids Using One‐Pot Multicomponent Reaction

Abstract

A facile multicomponent synthesis of novel thiazolidinone-bis Schiff base hybrids has been developed using readily available starting materials. The four-component reaction of isothiocyanate, hydrazine, aldehyde and αbromoester in water readily affords thiazolidinone-bis Schiff base hybrids, whereas the five-component strategy involving the same reactants in the presence of boron trifluoride etherate in acetonitrile leads to the formation of the fully functionalized thiazolidinone-bis Schiff base hybrids.

Anticorrosion Investigation of New Diazene-Based Schiff Base Derivatives as Safe Corrosion Inhibitors for API X65 Steel Pipelines in Acidic Oilfield Formation Water: Synthesis, Experimental, and Computational Studies

“…FTIR chart of compounds S1 and S2 displayed a broad peak at 3500 cm –1 attributed to the hydroxyl group, and two bands at 2920 cm –1 and 2850 cm –1 assigned to CH asymmetric and symmetric stretching vibration, as well as the band at 1600 cm –1 , corresponding to −CN– (azomethine group), the appearance of this band in the FTIR chart donated good evidence to the formation of the Schiff base group, and this result was confirmed by the disappearance of the band at 1700 cm –1 for the carbonyl group of the start compound , 13 C NMR: δ ppm = 14.2 (terminal aliphatic CH 3 ), 22–32 (aliphatic CH 2 ), 62.1 (aliphatic N–CH 2 ), 118.5 (CN), 122–132 (aromatic CH), 157.1 (C–N), 157.6 (CHN), 164.1 (C–OH).…”

“… 31 1 H NMR of S1 (400 MHz, CDCl 3 ) δ: 0.85 (3H, terminal C H 3 ), 1.3 (8H, aliphatic methylene units 4C H 2 ), 3.8 (2H, aliphatic methylene unit attached to nitrogen atom =N–C H 2 ), 7–9 (7H, attached to the aromatic rings and 1H for C H =N), and 11.2 (1H for the O H group). 32 , 33 13 C NMR: δ ppm = 14.2 (terminal aliphatic CH 3 ), 22–32 (aliphatic CH 2 ), 62.1 (aliphatic N–CH 2 ), 118.5 (C≡N), 122–132 (aromatic CH), 157.1 (C–N), 157.6 (CH=N), 164.1 (C–OH).…”

I2‐Promoted [3+2] Cyclization of Thiocarbamates with Enaminones: a Protocol for the Synthesis of Polysubstituted Thiazol‐2(3H)‐ones

“…The former method involved an I 2 -mediated annulation reaction from 1,3-diketones and potassium thiocyanate under transition-metal-free conditions, [7] while the latter one was an heteroannulation reaction under controlled microwave irradiation heating. [8] Guo and co-workers developed a facile access to benzo[d]thiazol-2(3H)-thiones and benzo[d]thiazol-2(3H)-ones through a temperature-controlled intermolecular [3 + 2] annulation in the presence of DMSO (Scheme 1c). [9] In 2022, the Saikia group successfully developed an efficient methodology for the synthesis of substituted thiazolones via [3,3]-sigmatropic rearrangement/5-exo-dig cyclization (Scheme 1d).…”

“…Yan and Singh almost simultaneously pioneered the synthesis of thiazol‐2(3 H )‐ones starting from thiocyanic/isothiocyanic derivatives (Scheme 1a, 1b). The former method involved an I 2 ‐mediated annulation reaction from 1,3‐diketones and potassium thiocyanate under transition‐metal‐free conditions, [7] while the latter one was an heteroannulation reaction under controlled microwave irradiation heating [8] . Guo and co‐workers developed a facile access to benzo[ d ]thiazol‐2(3 H )‐thiones and benzo[ d ]thiazol‐2(3 H )‐ones through a temperature‐controlled intermolecular [3+2] annulation in the presence of DMSO (Scheme 1c) [9] .…”