General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HR... more General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HRMS Data of Compounds 5 Crystallography data of 3f, 3j and 3q
The direct α‐Csp2H functionalization and thiomethylation of α‐oxoketene dithioacetals (DTAs) has... more The direct α‐Csp2H functionalization and thiomethylation of α‐oxoketene dithioacetals (DTAs) has been accomplished with dimethyl sulfoxide (DMSO) in the presence of iodine and a copper(I) salt for the first time. A prerequisite is the in situ iodination of the α‐Csp2 atom of dithioacetals that could offer other reaction channels. The operationally simple one‐pot protocol includes region‐defined consecutive iodination and sulfenylation of the challenging α‐Csp2H bond of dithioacetals employing cheap and readily available reagents. DMSO here plays a dual role as thiomethyl source and solvent.magnified image
A convenient and one-pot synthesis of 3-aroyl/heteroaroyl-2H-chromene-2-thiones and benzo[f]2Hchr... more A convenient and one-pot synthesis of 3-aroyl/heteroaroyl-2H-chromene-2-thiones and benzo[f]2Hchromene-2-thiones has been developed by the condensation of b-oxodithioesters and salicylaldehydes/ a-hydroxynaphthaldehydes in the presence of indium trichloride under solvent-free conditions. The reaction is operationally facile, readily scalable, and offers rapid entry into differentially substituted chromene-2-thione scaffolds.
hydroxanthene-1,8-diones has been developed by one-pot reaction of dimedone with aldehydes in the... more hydroxanthene-1,8-diones has been developed by one-pot reaction of dimedone with aldehydes in the presence of InCl 3 or P 2 O 5 under solvent-free conditions. The optical behaviors of the xanthenediones have been investigated by UVevis and fluorescence spectroscopy. The present approach offers the advantages of simple methodology, clean and mild reaction, high atom-economy, short reaction time, low environmental impact, wide substrate scope, high yield, and excellent purity.
European Journal of Organic Chemistry, May 16, 2013
One-Pot Three-Component Heteroannulation of β-Oxo Dithioesters, Amines and Hydroxylamine: Regiose... more One-Pot Three-Component Heteroannulation of β-Oxo Dithioesters, Amines and Hydroxylamine: Regioselective, Facile and Straightforward Entry to 5-Substituted 3-A highly regioselective synthesis of 5-sub-in situ generated β-oxo thioamide inter-Aminoisoxazoles stituted 3-aminoisoxazoles has been mediate. The mechanism of the reaction achieved by a one-pot three-component has been established experimentally and Keywords: Amines / Multicomponent reaccoupling of β-oxo dithioesters, amines and shown to be in agreement with the HSAB tions / Heteroannulation / Heterocycles / hydroxylamine in ethanol at reflux via an theory. Regioselectivity
An operationally simple, economical, and straightforward synthesis of diverse 4,5-disubstituted 1... more An operationally simple, economical, and straightforward synthesis of diverse 4,5-disubstituted 1,2,3-thiadiazoles from α-enolicdithioesters has been achieved via nitrosation/reduction/diazotization/cyclization sequence in one-pot through the formation of cascade 1–2 (N–S) and 3–4 (C–N) bonds. Importantly, this is the first straightforward entry to highly functionalized 1,2,3-thiadiazoles from dithioesters.
Table of contents 1 Experimental section 1.1 General 1.2 General procedure 1.3 Experimental Data ... more Table of contents 1 Experimental section 1.1 General 1.2 General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HRMS Data of Compounds 5 Crystallography data of 3e, 3r and A
Catalyst-free one-pot sustainable synthesis of thiazoloquinoline and thiazolopyridine scaffolds i... more Catalyst-free one-pot sustainable synthesis of thiazoloquinoline and thiazolopyridine scaffolds is achievedviafour-component domino reactions in water–PEG.
Abstract An operationally simple and facile synthesis of α-hydroxyimino-β-oxodithioesters has bee... more Abstract An operationally simple and facile synthesis of α-hydroxyimino-β-oxodithioesters has been achieved by nitrosation of α-enolicdithioesters. They were further treated with internal alkynes to afford diverse 1,4-thiazin-3-ones via domino reduction/annulation strategy under mild reaction conditions. Importantly, this is the first straightforward entry to highly functionalized 1,4-thiazin-3-one derivatives from simple starting materials.
Please note that technical editing may introduce minor changes to the text and/or graphics, which... more Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal's standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains.
DABCO-Promoted Three-Component Reaction Between Amines, Dialkyl Acetylenedicarboxylates, and Glyo... more DABCO-Promoted Three-Component Reaction Between Amines, Dialkyl Acetylenedicarboxylates, and Glyoxal.-Highly substituted pyrrole derivatives are readily available in one pot with good to excellent yields.-(RAMESH, K.; MURTHY, S.
Eco-Efficient, Regioselective and Rapid Access to 4,5-Disubstituted 1,2,3-Thiadiazoles via [3 + 2... more Eco-Efficient, Regioselective and Rapid Access to 4,5-Disubstituted 1,2,3-Thiadiazoles via [3 + 2] Cycloaddition of α-Enolicdithioesters with Tosyl Azide under Solvent-Free Conditions.-The title reaction is assumed to proceed via azide transfer from tosyl azide to dithio esters (I) followed by Wolff-type heterocyclization.-(SINGH*,
One-pot domino reactions Solvent-free conditions Metal-free P 2 O 5 a b s t r a c t Operationally... more One-pot domino reactions Solvent-free conditions Metal-free P 2 O 5 a b s t r a c t Operationally and user-simple a highly efficient one-pot three-component (5 molecules) coupling of aenolic dithioesters, cysteamine hydrochloride and aldehydes afforded a range of thiazolopyridines in high yields under metal-free and solvent-free conditions. The new domino protocol generated two rings by the concomitant formation of seven multiple bonds (two CeC, three CeN and two CeS) involving a sequence of N,S-acetal formation/double Michael addition/N-cyclization as key steps in a single operation.
General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HR... more General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HRMS Data of Compounds 5 Crystallography data of 3f, 3j and 3q
The direct α‐Csp2H functionalization and thiomethylation of α‐oxoketene dithioacetals (DTAs) has... more The direct α‐Csp2H functionalization and thiomethylation of α‐oxoketene dithioacetals (DTAs) has been accomplished with dimethyl sulfoxide (DMSO) in the presence of iodine and a copper(I) salt for the first time. A prerequisite is the in situ iodination of the α‐Csp2 atom of dithioacetals that could offer other reaction channels. The operationally simple one‐pot protocol includes region‐defined consecutive iodination and sulfenylation of the challenging α‐Csp2H bond of dithioacetals employing cheap and readily available reagents. DMSO here plays a dual role as thiomethyl source and solvent.magnified image
A convenient and one-pot synthesis of 3-aroyl/heteroaroyl-2H-chromene-2-thiones and benzo[f]2Hchr... more A convenient and one-pot synthesis of 3-aroyl/heteroaroyl-2H-chromene-2-thiones and benzo[f]2Hchromene-2-thiones has been developed by the condensation of b-oxodithioesters and salicylaldehydes/ a-hydroxynaphthaldehydes in the presence of indium trichloride under solvent-free conditions. The reaction is operationally facile, readily scalable, and offers rapid entry into differentially substituted chromene-2-thione scaffolds.
hydroxanthene-1,8-diones has been developed by one-pot reaction of dimedone with aldehydes in the... more hydroxanthene-1,8-diones has been developed by one-pot reaction of dimedone with aldehydes in the presence of InCl 3 or P 2 O 5 under solvent-free conditions. The optical behaviors of the xanthenediones have been investigated by UVevis and fluorescence spectroscopy. The present approach offers the advantages of simple methodology, clean and mild reaction, high atom-economy, short reaction time, low environmental impact, wide substrate scope, high yield, and excellent purity.
European Journal of Organic Chemistry, May 16, 2013
One-Pot Three-Component Heteroannulation of β-Oxo Dithioesters, Amines and Hydroxylamine: Regiose... more One-Pot Three-Component Heteroannulation of β-Oxo Dithioesters, Amines and Hydroxylamine: Regioselective, Facile and Straightforward Entry to 5-Substituted 3-A highly regioselective synthesis of 5-sub-in situ generated β-oxo thioamide inter-Aminoisoxazoles stituted 3-aminoisoxazoles has been mediate. The mechanism of the reaction achieved by a one-pot three-component has been established experimentally and Keywords: Amines / Multicomponent reaccoupling of β-oxo dithioesters, amines and shown to be in agreement with the HSAB tions / Heteroannulation / Heterocycles / hydroxylamine in ethanol at reflux via an theory. Regioselectivity
An operationally simple, economical, and straightforward synthesis of diverse 4,5-disubstituted 1... more An operationally simple, economical, and straightforward synthesis of diverse 4,5-disubstituted 1,2,3-thiadiazoles from α-enolicdithioesters has been achieved via nitrosation/reduction/diazotization/cyclization sequence in one-pot through the formation of cascade 1–2 (N–S) and 3–4 (C–N) bonds. Importantly, this is the first straightforward entry to highly functionalized 1,2,3-thiadiazoles from dithioesters.
Table of contents 1 Experimental section 1.1 General 1.2 General procedure 1.3 Experimental Data ... more Table of contents 1 Experimental section 1.1 General 1.2 General procedure 1.3 Experimental Data 2 References 3 1 H and 13 C NMR spectra of Compounds 4 HRMS Data of Compounds 5 Crystallography data of 3e, 3r and A
Catalyst-free one-pot sustainable synthesis of thiazoloquinoline and thiazolopyridine scaffolds i... more Catalyst-free one-pot sustainable synthesis of thiazoloquinoline and thiazolopyridine scaffolds is achievedviafour-component domino reactions in water–PEG.
Abstract An operationally simple and facile synthesis of α-hydroxyimino-β-oxodithioesters has bee... more Abstract An operationally simple and facile synthesis of α-hydroxyimino-β-oxodithioesters has been achieved by nitrosation of α-enolicdithioesters. They were further treated with internal alkynes to afford diverse 1,4-thiazin-3-ones via domino reduction/annulation strategy under mild reaction conditions. Importantly, this is the first straightforward entry to highly functionalized 1,4-thiazin-3-one derivatives from simple starting materials.
Please note that technical editing may introduce minor changes to the text and/or graphics, which... more Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal's standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains.
DABCO-Promoted Three-Component Reaction Between Amines, Dialkyl Acetylenedicarboxylates, and Glyo... more DABCO-Promoted Three-Component Reaction Between Amines, Dialkyl Acetylenedicarboxylates, and Glyoxal.-Highly substituted pyrrole derivatives are readily available in one pot with good to excellent yields.-(RAMESH, K.; MURTHY, S.
Eco-Efficient, Regioselective and Rapid Access to 4,5-Disubstituted 1,2,3-Thiadiazoles via [3 + 2... more Eco-Efficient, Regioselective and Rapid Access to 4,5-Disubstituted 1,2,3-Thiadiazoles via [3 + 2] Cycloaddition of α-Enolicdithioesters with Tosyl Azide under Solvent-Free Conditions.-The title reaction is assumed to proceed via azide transfer from tosyl azide to dithio esters (I) followed by Wolff-type heterocyclization.-(SINGH*,
One-pot domino reactions Solvent-free conditions Metal-free P 2 O 5 a b s t r a c t Operationally... more One-pot domino reactions Solvent-free conditions Metal-free P 2 O 5 a b s t r a c t Operationally and user-simple a highly efficient one-pot three-component (5 molecules) coupling of aenolic dithioesters, cysteamine hydrochloride and aldehydes afforded a range of thiazolopyridines in high yields under metal-free and solvent-free conditions. The new domino protocol generated two rings by the concomitant formation of seven multiple bonds (two CeC, three CeN and two CeS) involving a sequence of N,S-acetal formation/double Michael addition/N-cyclization as key steps in a single operation.
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