Dattatraya Dethe - Academia.edu (original) (raw)
Papers by Dattatraya Dethe
ChemInform, Sep 2, 2008
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Journal of Organic Chemistry, Mar 10, 2022
Herein, we report the asymmetric Ru/cinchonine dual catalysis that provides straightforward acces... more Herein, we report the asymmetric Ru/cinchonine dual catalysis that provides straightforward access to enantioselective synthesis of C-3 substituted phthalides via tandem C-H activation/Michael addition cascade. The use of readily accessible and less expensive [RuCl2(p-cym)]2 and cinchonine catalyst for the one-pot assembly of chiral phthalides greatly overcomes the present trend of using highly sophisticated catalysts. The developed method provides access to both enantiomers of a product using pseudoenantiomeric cinchona alkaloids as catalysts streamlining the synthesis of phthalide in both the optically active forms.
Journal of Organic Chemistry, Apr 17, 2015
A one step protocol has been developed for the enantioselective synthesis of hexahydrodibenzofura... more A one step protocol has been developed for the enantioselective synthesis of hexahydrodibenzofuran derivatives using a modified Friedel-Crafts reaction. The developed method was applied to the synthesis of a series of natural products including (+)-hostmanin A, (+)-methyllinderatin, and (-linderol A. The synthetic and spectroscopic data investigations led to the structural reassignment of natural product adunctin-E, which was further confirmed by single crystal X-ray analysis.
Organic Letters, Jan 16, 2018
(-)-Siccanin (1), a natural product possessing significant antifungal properties, was synthesized... more (-)-Siccanin (1), a natural product possessing significant antifungal properties, was synthesized enantioselectively via a biomimetic route. This synthetic route features two sequential radical cyclizations: a Ti(III)-mediated radical cyclization of epoxyolefin 48 to construct the Bring , and a Suarez reaction to establish the tetrahyrofuran ring. Chiral chroman moiety of siccanin was prepared based on our recent development of the Pd-catalyzed asymmetric allylic alkylation (AAA) of phenol trisubstituted allyl carbonates. Several other members of the siccanin family were also synthesized including siccanochromenes A (2), B (3), E (6), F (7), and the methyl ether of siccanochromene C (55). These studies may shed light on the biosynthesis of this novel family of compounds.
Organic Letters, Mar 17, 2021
An efficient and convergent first total syntheses of (±)-japonicol B and (-)-japonicol C have bee... more An efficient and convergent first total syntheses of (±)-japonicol B and (-)-japonicol C have been completed. The notable points of the synthetic route are Lewis-acid-catalyzed Friedel-Crafts reaction for one pot C-C and C-O bond formations resulting in construction of the tricyclic meroterpenoid skeleton, one pot Pd(OH)2/C-catalyzed isomerization/hydrogenation, and site selective sp3 C-H oxidation.
European Journal of Organic Chemistry, Apr 17, 2015
"One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grind... more "One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grindstone Technology.-Two simple, novel and ecofriendly protocols for the synthesis of title compounds (III) are developed.-(GUPTA*, R.;
Chemistry: A European Journal, Nov 25, 2015
Pd-catalyseda nnulation reactions between indole derivatives andi nternal alkynee sters leadingt ... more Pd-catalyseda nnulation reactions between indole derivatives andi nternal alkynee sters leadingt o variousp yrrolo[1,2-a]indoles and pyrroloquinolines have been developed. The strategy involves an intermolecular additiono ft he indole nitrogeno nt ot he internal alkyne ester followed by an intramolecular insertion of av inylpalladium complex into the carbonyl group. This method offersafacile and practical approacht op yrrolo[1,2-a]indoles and pyrroloquinolines.
Journal of Organic Chemistry, Feb 20, 2018
Total synthesis of (±)-adunctin B, a natural product isolated from Piper aduncum (Piperaceae), ha... more Total synthesis of (±)-adunctin B, a natural product isolated from Piper aduncum (Piperaceae), has been achieved using two different strategies, in seven and three steps. The efficient approach features highly atom economical and diastereoselective Friedel-Crafts acylation, alkylation reaction and palladium catalyzed Wacker type oxidative cyclization.
Organic Letters, Mar 11, 2022
A formal synthesis of FR252921, a potent macrocyclic immunosuppressive agent, and a six-step synt... more A formal synthesis of FR252921, a potent macrocyclic immunosuppressive agent, and a six-step synthesis of vitamin A have been demonstrated. The application of a ruthenium-catalyzed step-economic and environmentally benign strategy for the highly stereo- and chemoselective construction of valuable polyene motifs of FR252921 and vitamin A highlights the syntheses. The key features for the synthesis FR252921 include preparation of the triene moiety followed by two consecutive peptide couplings of the three fragments.
Organic and Biomolecular Chemistry, 2016
The strategy was further applied for the synthesis of optically active pyrrolo[1,2-a]indoles in &... more The strategy was further applied for the synthesis of optically active pyrrolo[1,2-a]indoles in >97% de using the chiral auxiliary based approach.
Organic Letters, Jan 27, 2020
Ru-catalyzed oxidative coupling of allyl alcohols and activated olefins has been developed by C(a... more Ru-catalyzed oxidative coupling of allyl alcohols and activated olefins has been developed by C(allyl)-H activation of allyl alcohols providing efficient and direct access to synthetically useful α,β-unsaturated enone intermediates. Synthetic utility of this method was demonstrated by its application to synthesis of bioactive natural products such as Hydroxy-β-sanshool, ZP-amide I, Chondrillin, Plakorin, and (+)-cis-Solamin A.
Chemical Communications, 2015
Preparation of chiral ligand 2d: S2 General procedure for asymmetric alkynylation of aliphatic al... more Preparation of chiral ligand 2d: S2 General procedure for asymmetric alkynylation of aliphatic aldehydes: S3 -hydroxy-,-acetylenic esters 1a-d: S4 General procedure for asymmetric alkynylation of aromatic aldehydes: S5 -hydroxy-,-acetylenic esters 1e-k: S5 Conversion of ethyl ester 1e into the known methyl ester S3 to determine the stereochemistry: S8 Conversion of alkynes 1f-j into allyl alcohols S4-6 in order to determine the stereochemistry by the modified Mosher method: S8 Preparation of MTPA esters S7-12: S9 Determination of the stereochemistry of allyl alcohols S4-6 by the modified Mosher method: S11 References: 1 H NMR/ 13 C NMR Spectra: S12 Generals: Melting points are uncorrected. Optical rotations were measured by using a JASCO P-1020 digital polarimeter. 1 H NMR spectra were recorded in CDCl 3 solution with a JEOL JNM-GX-500 spectrometer (500 MHz) or a JEOL JNM-ECS400 (400 MHz). 13 C NMR spectra were recorded in CDCl 3 solution with a JEOL JNM-ECS400 (100 MHz) or a JNM-GX-500 (125 MHz). All signals are expressed as values in ppm downfield from the internal standard tetramethylsilane. The following abbreviations are used: broad = br, singlet = s, doublet = d, triplet = t, quartet = q, quintet = qn and multiplet = m. IR absorption spectra (FT = diffuse reflectance spectroscopy) were recorded for samples loaded as neat films on NaCl plates by using a Shimazu FTIR-8400S and only noteworthy absorptions (in cm 1) are listed. Mass spectra were obtained with a JEOL JMS-600H or a JEOL JMS-700 mass spectrometer. Column chromatography was carried out by using Kanto Chemical silica gel 60N (spherical, neutral, 63-210 m) and flash column chromatography was carried out by using Merck silica gel 60 (40-63 m). All air-or moisture-sensitive reactions were
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Journal of Organic Chemistry, Oct 10, 2019
A full account on the first total synthesis of chroman meroterpenoid, (-)-phomoarcherin C has bee... more A full account on the first total synthesis of chroman meroterpenoid, (-)-phomoarcherin C has been described. Key synthetic transformations include phenyl boronic acid mediated 6π-electrocyclization reaction, a stereospecific hydrogenation driven by thermodynamic, conformational stability of the product and regioselective formylation. The strategy employed is considerably short, atom economical and can open the doors to provide access to various other natural products of the kind.
ChemInform, Aug 27, 2015
"One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grind... more "One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grindstone Technology.-Two simple, novel and ecofriendly protocols for the synthesis of title compounds (III) are developed.-(GUPTA*, R.;
ChemInform, Sep 2, 2008
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Journal of Organic Chemistry, Mar 10, 2022
Herein, we report the asymmetric Ru/cinchonine dual catalysis that provides straightforward acces... more Herein, we report the asymmetric Ru/cinchonine dual catalysis that provides straightforward access to enantioselective synthesis of C-3 substituted phthalides via tandem C-H activation/Michael addition cascade. The use of readily accessible and less expensive [RuCl2(p-cym)]2 and cinchonine catalyst for the one-pot assembly of chiral phthalides greatly overcomes the present trend of using highly sophisticated catalysts. The developed method provides access to both enantiomers of a product using pseudoenantiomeric cinchona alkaloids as catalysts streamlining the synthesis of phthalide in both the optically active forms.
Journal of Organic Chemistry, Apr 17, 2015
A one step protocol has been developed for the enantioselective synthesis of hexahydrodibenzofura... more A one step protocol has been developed for the enantioselective synthesis of hexahydrodibenzofuran derivatives using a modified Friedel-Crafts reaction. The developed method was applied to the synthesis of a series of natural products including (+)-hostmanin A, (+)-methyllinderatin, and (-linderol A. The synthetic and spectroscopic data investigations led to the structural reassignment of natural product adunctin-E, which was further confirmed by single crystal X-ray analysis.
Organic Letters, Jan 16, 2018
(-)-Siccanin (1), a natural product possessing significant antifungal properties, was synthesized... more (-)-Siccanin (1), a natural product possessing significant antifungal properties, was synthesized enantioselectively via a biomimetic route. This synthetic route features two sequential radical cyclizations: a Ti(III)-mediated radical cyclization of epoxyolefin 48 to construct the Bring , and a Suarez reaction to establish the tetrahyrofuran ring. Chiral chroman moiety of siccanin was prepared based on our recent development of the Pd-catalyzed asymmetric allylic alkylation (AAA) of phenol trisubstituted allyl carbonates. Several other members of the siccanin family were also synthesized including siccanochromenes A (2), B (3), E (6), F (7), and the methyl ether of siccanochromene C (55). These studies may shed light on the biosynthesis of this novel family of compounds.
Organic Letters, Mar 17, 2021
An efficient and convergent first total syntheses of (±)-japonicol B and (-)-japonicol C have bee... more An efficient and convergent first total syntheses of (±)-japonicol B and (-)-japonicol C have been completed. The notable points of the synthetic route are Lewis-acid-catalyzed Friedel-Crafts reaction for one pot C-C and C-O bond formations resulting in construction of the tricyclic meroterpenoid skeleton, one pot Pd(OH)2/C-catalyzed isomerization/hydrogenation, and site selective sp3 C-H oxidation.
European Journal of Organic Chemistry, Apr 17, 2015
"One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grind... more "One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grindstone Technology.-Two simple, novel and ecofriendly protocols for the synthesis of title compounds (III) are developed.-(GUPTA*, R.;
Chemistry: A European Journal, Nov 25, 2015
Pd-catalyseda nnulation reactions between indole derivatives andi nternal alkynee sters leadingt ... more Pd-catalyseda nnulation reactions between indole derivatives andi nternal alkynee sters leadingt o variousp yrrolo[1,2-a]indoles and pyrroloquinolines have been developed. The strategy involves an intermolecular additiono ft he indole nitrogeno nt ot he internal alkyne ester followed by an intramolecular insertion of av inylpalladium complex into the carbonyl group. This method offersafacile and practical approacht op yrrolo[1,2-a]indoles and pyrroloquinolines.
Journal of Organic Chemistry, Feb 20, 2018
Total synthesis of (±)-adunctin B, a natural product isolated from Piper aduncum (Piperaceae), ha... more Total synthesis of (±)-adunctin B, a natural product isolated from Piper aduncum (Piperaceae), has been achieved using two different strategies, in seven and three steps. The efficient approach features highly atom economical and diastereoselective Friedel-Crafts acylation, alkylation reaction and palladium catalyzed Wacker type oxidative cyclization.
Organic Letters, Mar 11, 2022
A formal synthesis of FR252921, a potent macrocyclic immunosuppressive agent, and a six-step synt... more A formal synthesis of FR252921, a potent macrocyclic immunosuppressive agent, and a six-step synthesis of vitamin A have been demonstrated. The application of a ruthenium-catalyzed step-economic and environmentally benign strategy for the highly stereo- and chemoselective construction of valuable polyene motifs of FR252921 and vitamin A highlights the syntheses. The key features for the synthesis FR252921 include preparation of the triene moiety followed by two consecutive peptide couplings of the three fragments.
Organic and Biomolecular Chemistry, 2016
The strategy was further applied for the synthesis of optically active pyrrolo[1,2-a]indoles in &... more The strategy was further applied for the synthesis of optically active pyrrolo[1,2-a]indoles in >97% de using the chiral auxiliary based approach.
Organic Letters, Jan 27, 2020
Ru-catalyzed oxidative coupling of allyl alcohols and activated olefins has been developed by C(a... more Ru-catalyzed oxidative coupling of allyl alcohols and activated olefins has been developed by C(allyl)-H activation of allyl alcohols providing efficient and direct access to synthetically useful α,β-unsaturated enone intermediates. Synthetic utility of this method was demonstrated by its application to synthesis of bioactive natural products such as Hydroxy-β-sanshool, ZP-amide I, Chondrillin, Plakorin, and (+)-cis-Solamin A.
Chemical Communications, 2015
Preparation of chiral ligand 2d: S2 General procedure for asymmetric alkynylation of aliphatic al... more Preparation of chiral ligand 2d: S2 General procedure for asymmetric alkynylation of aliphatic aldehydes: S3 -hydroxy-,-acetylenic esters 1a-d: S4 General procedure for asymmetric alkynylation of aromatic aldehydes: S5 -hydroxy-,-acetylenic esters 1e-k: S5 Conversion of ethyl ester 1e into the known methyl ester S3 to determine the stereochemistry: S8 Conversion of alkynes 1f-j into allyl alcohols S4-6 in order to determine the stereochemistry by the modified Mosher method: S8 Preparation of MTPA esters S7-12: S9 Determination of the stereochemistry of allyl alcohols S4-6 by the modified Mosher method: S11 References: 1 H NMR/ 13 C NMR Spectra: S12 Generals: Melting points are uncorrected. Optical rotations were measured by using a JASCO P-1020 digital polarimeter. 1 H NMR spectra were recorded in CDCl 3 solution with a JEOL JNM-GX-500 spectrometer (500 MHz) or a JEOL JNM-ECS400 (400 MHz). 13 C NMR spectra were recorded in CDCl 3 solution with a JEOL JNM-ECS400 (100 MHz) or a JNM-GX-500 (125 MHz). All signals are expressed as values in ppm downfield from the internal standard tetramethylsilane. The following abbreviations are used: broad = br, singlet = s, doublet = d, triplet = t, quartet = q, quintet = qn and multiplet = m. IR absorption spectra (FT = diffuse reflectance spectroscopy) were recorded for samples loaded as neat films on NaCl plates by using a Shimazu FTIR-8400S and only noteworthy absorptions (in cm 1) are listed. Mass spectra were obtained with a JEOL JMS-600H or a JEOL JMS-700 mass spectrometer. Column chromatography was carried out by using Kanto Chemical silica gel 60N (spherical, neutral, 63-210 m) and flash column chromatography was carried out by using Merck silica gel 60 (40-63 m). All air-or moisture-sensitive reactions were
Journal of Organic Chemistry, Oct 10, 2019
A full account on the first total synthesis of chroman meroterpenoid, (-)-phomoarcherin C has bee... more A full account on the first total synthesis of chroman meroterpenoid, (-)-phomoarcherin C has been described. Key synthetic transformations include phenyl boronic acid mediated 6π-electrocyclization reaction, a stereospecific hydrogenation driven by thermodynamic, conformational stability of the product and regioselective formylation. The strategy employed is considerably short, atom economical and can open the doors to provide access to various other natural products of the kind.
ChemInform, Aug 27, 2015
"One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grind... more "One-Pot" Synthesis of 2-Amino-3-cyano-4,6-diarylpyridines under Ultrasonic Irradiation and Grindstone Technology.-Two simple, novel and ecofriendly protocols for the synthesis of title compounds (III) are developed.-(GUPTA*, R.;