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Papers by Shankar Hangirgekar
Applied Organometallic Chemistry
![Research paper thumbnail of An Efficient Protocol for the Synthesis of Pyrido[2,3‐d]pyrimidines in Glycerol–Water Medium: Assessment by Green Chemistry Metrics](https://attachments.academia-assets.com/105908529/thumbnails/1.jpg)
](Macromolecular Symposia, 2019
A clean and ecofriendly approach for the catalyst‐free synthesis of pyrido[2,3‐d]pyrimidine deriv... more A clean and ecofriendly approach for the catalyst‐free synthesis of pyrido[2,3‐d]pyrimidine derivatives by one‐pot three‐component condensation of aromatic aldehyde, malononitrile and 6‐aminouracil or 6‐amino‐1,3‐dimethyluracil using glycerol–water (3:1) as green reaction media has been developed. Catalyst‐free synthesis with high to excellent yields and use of glycerol–water system as an environmentally benign reaction condition are the prominent features of this strategy. Moreover, excellent outcomes from the calculations of green chemistry metrics reveal the greenness of the protocol.
Journal of Molecular Structure
Marine Policy, 2002
... There has been a noticeable shift in emphasis away from environmental regulation to prevent ... more ... There has been a noticeable shift in emphasis away from environmental regulation to prevent marine pollution towards calls for clean technologies, zero discharge, and the adoption of the precautionary principle and BEP and BAT. ... 4. Living resources. 4.1. Fish farming. Fig. ...
Journal of Catalysts, 2015
ZSM-5 zeolite was synthesized by sourcing silica from wheat husk ash and was converted into its p... more ZSM-5 zeolite was synthesized by sourcing silica from wheat husk ash and was converted into its protonated form following careful, conventionally accepted ion-exchange method and calcinations. The H-ZSM-5 zeolite (Si/Al ratio = 30) prepared was appropriately characterized by XRD, FT-IR, SEM, TEM, TG-DTA, CV, and so forth, and evaluated as recyclable catalyst in selective organic transformations including three- and four-component reactions. The catalytic activity of the zeolite sample supposedly relates to increased density of the accessible acid sites.
Three component condensation of 1,2-dicarbonyl compound, aldehyde and ammonium acetate under micr... more Three component condensation of 1,2-dicarbonyl compound, aldehyde and ammonium acetate under microwave irradiation in presence of cupric chloride (CuCl 2 .2H 2 O) as a catalyst give corresponding 2,4,5-trisubstituted imidazole's. The key advantages of this process are reaction proceeded smoothly and product obtained in excellent yield with high purity, cost effectiveness of catalyst, easy work-up.
Applied Organometallic Chemistry
Zn(NO 3) 2 as an efficient catalyst have been used for the one-pot synthesis of 1,8-Dioxooctahydr... more Zn(NO 3) 2 as an efficient catalyst have been used for the one-pot synthesis of 1,8-Dioxooctahydroxanthene Derivatives via multi-component reactions between dimedone and various aromatic aldehydes under solvent-free conditions. The presented method is available, environmentally friendly, cheap and highly effective to give the products in good to excellent yields.
(Z, Z, E)-7, 11, 13-Hexadecatrienal, the major component of the sex pheromone of the citrus leaf ... more (Z, Z, E)-7, 11, 13-Hexadecatrienal, the major component of the sex pheromone of the citrus leaf miner Phyllocnistis citrella is efficiently and stereoselectively synthesized starting from the commercially available 6-Bromo-1-hexanol and described hereby. The synthesis of (Z, Z, E)-7, 11, 13-Hexadecatrienal was carried out by using the key step being Wittig reaction of the protected ylide using potassium tertiary butoxide a base to furnish 11Z double bond (Z)-isomer as the major product. The stereoselective formation of the 7Z double bond is formed by the stereospecific reduction of internal alkyne with sodium borohydride (PIINi). The synthetic methodology is inexpensive with its operational simplicity and it will be attractive for academic and industrial research.
A simple and practical procedure for aqueous phase reaction of various α-tosyloxy ketones with 2-... more A simple and practical procedure for aqueous phase reaction of various α-tosyloxy ketones with 2- amino pyridine and their derivatives in the presence of β-Cyclodextrin has been developed to furnish bridgehead azaheterocycles 3a-h & 4a-d in good to excellent yields.
Preparative Biochemistry & Biotechnology, 2012
[BPy]H(2)PO(4) was easily prepared and used as an efficient and recyclable catalyst for the one-p... more [BPy]H(2)PO(4) was easily prepared and used as an efficient and recyclable catalyst for the one-pot synthesis of 2,4,5-trisubstituted imidazoles under solvent-free conditions in good to excellent yields. Solvent-free conditions, simple experimental and workup procedures, and the use of a nontoxic, recyclable catalyst of an environmentally benign nature are remarkable features of the procedure.
international journal of chemical sciences, 2010
An efficient and facile route for the synthesis of coumarins via the Pechmann reaction catalyzed ... more An efficient and facile route for the synthesis of coumarins via the Pechmann reaction catalyzed by L-proline has been described. The reaction proceeded in dichloromethane at room temperature with good to excellent yields.
The persimmon (Persimon) is an edible fruit of trees in the genus Diospyros. Persimmon (Diospyros... more The persimmon (Persimon) is an edible fruit of trees in the genus Diospyros. Persimmon (Diospyros kaki Thumb) is an important tree fruit belongs to family Ebenaceae [1]. This is the most significant deciduous fruit tree and the major producers are China, Korea, Japan, Brazil and Italy while U.S.A, India and Australia are the minor producers. In the midst of tree a fruit Persimmon is ranked first in Korea in terms of harvest area literature data reveals that in the year of 2012 almost 30,264 ha land was occupied [2]. Abstract The sex pheromone components of the Persimmon Fruit Moth (PFM) Stathmopoda masinissa, a dangerous persimmon pest in eastern Asia, (4E,6Z)-Hexadeca-4,6-dien-1-ol, (4E,6E)-Hexadeca-4,6-dienyl acetate and (4E,6Z)-Hexadeca-4,6-dienal, were synthesized stereoselectively and efficiently starting from commercially available starting materials. The stereoselective formation of (4E) double bond based on Hydroxymethylation of 4-(2 -tetrahydpyranyloxy)-1-pentyn prepared fr...
Developing sustainable methodologies using green solvents, reusable catalysts and energy saving a... more Developing sustainable methodologies using green solvents, reusable catalysts and energy saving approaches is the need of time considering the growing stringent environmental regulations. The present study reports the novel three-step synthesis of magnetically separable Fe3O4@SiO2-SO3H-DABCO core-shell magnetic nanocomposite catalyst and evaluation of its catalytic efficiency involving the synthesis of structurally diverse diheteroarylmethanes via one-pot reaction of indoles, aryl aldehydes and 4-hydroxycoumarin in aqueous ethanol (50:50 v/v) at ambient conditions. The catalyst could be recycled for six consecutive runs without significant change in catalytic activity or the product yields. The ecofriendly synthetic approach offers several advantages such as the use of a green solvent system, ambient reaction conditions, shorter reaction times, excellent yields and ease of separation of the catalyst using an external magnet.
Chemistry of Natural Compounds
Journal of Molecular Structure
![Research paper thumbnail of [MerDABCO-SO3H]Cl catalyzed synthesis, antimicrobial and antioxidant evaluation and molecular docking study of pyrazolopyranopyrimidines](https://attachments.academia-assets.com/72340723/thumbnails/1.jpg)
](Journal of Molecular Structure
Applied Organometallic Chemistry
Macromolecular Symposia, 2019
A clean and ecofriendly approach for the catalyst‐free synthesis of pyrido[2,3‐d]pyrimidine deriv... more A clean and ecofriendly approach for the catalyst‐free synthesis of pyrido[2,3‐d]pyrimidine derivatives by one‐pot three‐component condensation of aromatic aldehyde, malononitrile and 6‐aminouracil or 6‐amino‐1,3‐dimethyluracil using glycerol–water (3:1) as green reaction media has been developed. Catalyst‐free synthesis with high to excellent yields and use of glycerol–water system as an environmentally benign reaction condition are the prominent features of this strategy. Moreover, excellent outcomes from the calculations of green chemistry metrics reveal the greenness of the protocol.
Journal of Molecular Structure
Marine Policy, 2002
... There has been a noticeable shift in emphasis away from environmental regulation to prevent ... more ... There has been a noticeable shift in emphasis away from environmental regulation to prevent marine pollution towards calls for clean technologies, zero discharge, and the adoption of the precautionary principle and BEP and BAT. ... 4. Living resources. 4.1. Fish farming. Fig. ...
Journal of Catalysts, 2015
ZSM-5 zeolite was synthesized by sourcing silica from wheat husk ash and was converted into its p... more ZSM-5 zeolite was synthesized by sourcing silica from wheat husk ash and was converted into its protonated form following careful, conventionally accepted ion-exchange method and calcinations. The H-ZSM-5 zeolite (Si/Al ratio = 30) prepared was appropriately characterized by XRD, FT-IR, SEM, TEM, TG-DTA, CV, and so forth, and evaluated as recyclable catalyst in selective organic transformations including three- and four-component reactions. The catalytic activity of the zeolite sample supposedly relates to increased density of the accessible acid sites.
Three component condensation of 1,2-dicarbonyl compound, aldehyde and ammonium acetate under micr... more Three component condensation of 1,2-dicarbonyl compound, aldehyde and ammonium acetate under microwave irradiation in presence of cupric chloride (CuCl 2 .2H 2 O) as a catalyst give corresponding 2,4,5-trisubstituted imidazole's. The key advantages of this process are reaction proceeded smoothly and product obtained in excellent yield with high purity, cost effectiveness of catalyst, easy work-up.
Applied Organometallic Chemistry
Zn(NO 3) 2 as an efficient catalyst have been used for the one-pot synthesis of 1,8-Dioxooctahydr... more Zn(NO 3) 2 as an efficient catalyst have been used for the one-pot synthesis of 1,8-Dioxooctahydroxanthene Derivatives via multi-component reactions between dimedone and various aromatic aldehydes under solvent-free conditions. The presented method is available, environmentally friendly, cheap and highly effective to give the products in good to excellent yields.
(Z, Z, E)-7, 11, 13-Hexadecatrienal, the major component of the sex pheromone of the citrus leaf ... more (Z, Z, E)-7, 11, 13-Hexadecatrienal, the major component of the sex pheromone of the citrus leaf miner Phyllocnistis citrella is efficiently and stereoselectively synthesized starting from the commercially available 6-Bromo-1-hexanol and described hereby. The synthesis of (Z, Z, E)-7, 11, 13-Hexadecatrienal was carried out by using the key step being Wittig reaction of the protected ylide using potassium tertiary butoxide a base to furnish 11Z double bond (Z)-isomer as the major product. The stereoselective formation of the 7Z double bond is formed by the stereospecific reduction of internal alkyne with sodium borohydride (PIINi). The synthetic methodology is inexpensive with its operational simplicity and it will be attractive for academic and industrial research.
A simple and practical procedure for aqueous phase reaction of various α-tosyloxy ketones with 2-... more A simple and practical procedure for aqueous phase reaction of various α-tosyloxy ketones with 2- amino pyridine and their derivatives in the presence of β-Cyclodextrin has been developed to furnish bridgehead azaheterocycles 3a-h & 4a-d in good to excellent yields.
Preparative Biochemistry & Biotechnology, 2012
[BPy]H(2)PO(4) was easily prepared and used as an efficient and recyclable catalyst for the one-p... more [BPy]H(2)PO(4) was easily prepared and used as an efficient and recyclable catalyst for the one-pot synthesis of 2,4,5-trisubstituted imidazoles under solvent-free conditions in good to excellent yields. Solvent-free conditions, simple experimental and workup procedures, and the use of a nontoxic, recyclable catalyst of an environmentally benign nature are remarkable features of the procedure.
international journal of chemical sciences, 2010
An efficient and facile route for the synthesis of coumarins via the Pechmann reaction catalyzed ... more An efficient and facile route for the synthesis of coumarins via the Pechmann reaction catalyzed by L-proline has been described. The reaction proceeded in dichloromethane at room temperature with good to excellent yields.
The persimmon (Persimon) is an edible fruit of trees in the genus Diospyros. Persimmon (Diospyros... more The persimmon (Persimon) is an edible fruit of trees in the genus Diospyros. Persimmon (Diospyros kaki Thumb) is an important tree fruit belongs to family Ebenaceae [1]. This is the most significant deciduous fruit tree and the major producers are China, Korea, Japan, Brazil and Italy while U.S.A, India and Australia are the minor producers. In the midst of tree a fruit Persimmon is ranked first in Korea in terms of harvest area literature data reveals that in the year of 2012 almost 30,264 ha land was occupied [2]. Abstract The sex pheromone components of the Persimmon Fruit Moth (PFM) Stathmopoda masinissa, a dangerous persimmon pest in eastern Asia, (4E,6Z)-Hexadeca-4,6-dien-1-ol, (4E,6E)-Hexadeca-4,6-dienyl acetate and (4E,6Z)-Hexadeca-4,6-dienal, were synthesized stereoselectively and efficiently starting from commercially available starting materials. The stereoselective formation of (4E) double bond based on Hydroxymethylation of 4-(2 -tetrahydpyranyloxy)-1-pentyn prepared fr...
Developing sustainable methodologies using green solvents, reusable catalysts and energy saving a... more Developing sustainable methodologies using green solvents, reusable catalysts and energy saving approaches is the need of time considering the growing stringent environmental regulations. The present study reports the novel three-step synthesis of magnetically separable Fe3O4@SiO2-SO3H-DABCO core-shell magnetic nanocomposite catalyst and evaluation of its catalytic efficiency involving the synthesis of structurally diverse diheteroarylmethanes via one-pot reaction of indoles, aryl aldehydes and 4-hydroxycoumarin in aqueous ethanol (50:50 v/v) at ambient conditions. The catalyst could be recycled for six consecutive runs without significant change in catalytic activity or the product yields. The ecofriendly synthetic approach offers several advantages such as the use of a green solvent system, ambient reaction conditions, shorter reaction times, excellent yields and ease of separation of the catalyst using an external magnet.
Chemistry of Natural Compounds
Journal of Molecular Structure
Journal of Molecular Structure