‘Greener’Solventless or Benign Media Microwave-Assisted Methods from Varma’s Laboratory
• MW-assisted Synthesis – Catalytic Applications in Aqueous Media: Coordination Chem. Rev., 291, 68-94 (2015).
• MW-assisted Chemistry: Synth. Applications for Nanomaterials and Organics: Acc. Chem. Res., 47, 1338-1348 (2014).
• Solvent-free and Catalyst-free Chemistry–A Benign Pathway to Sustainability: ChemSusChem, 7, 24-44, (2014).
• Benign by Design: Catalyst-Free, In-water, On-water Green Organic Synthesis: Chem. Soc. Rev., 42, 5522-5551 (2013).
• Alternate Energy Input: Mechanochemical, MW- & Ultrasound in Org. Synthesis: Chem. Soc. Rev., 41, 1559 (2012).
• Green Chemistry by Nano-Catalysis: Green Chem., 12, 743 (2010); MW Ag Nano: Acc. Chem. Res., 44, 469 (2011).
• MW-assisted Rapid and Sustainable Route to Organics and Nanomaterials: Aust. J. Chem., 62, 16-26 (2009).
• Aqueous MW Chemistry: Green Synth. Tool for Rapid Drug Discovery, Chem. Soc. Rev, 37, 1546-1557 (2008)
• MW-assisted Organic Synthesis & Transformations in Benign Reaction Media: Acc. Chem. Res., 41, 629-639 (2008).
• Greener Syntheses of Heterocyclic Compounds Using Microwaves, Pure & Applied Chem., 80, 777-790 (2008).
• Syntheses Using Mechanochemical Mixing, Microwave- & Ultrasonic Irradiation, Green Chem Lett. Rev., 1, 37 (2008)
• Book: Alternate Energy Processes in Chem. Synth.-MW, Ultrasound and Photo Activation, Narosa Publ., Delhi, 2008.
• Sustainable Approach to Pharmaceutically Active Heterocycles: Curr. Opin. Drug Discov. Devel., 10, pp 723-737 (2007).
• Book Chapter: MW & Supported Reagents in Microwaves in Organic Synthesis, Wiley-VCH, Chap #8. pp 362-415 (2006)
• Book Chapter: MW in Green and Sustainable Chemistry in Top Curr Chem., Springer-Verlag, 266: pp 199-231 (2006)
• Book Chapter: Solventless Reactions in Green Separation Processes, Wiley-VCH, Chap 2.2. pp 53-87 (2005)
• MW Technology-Chemical Synth Applications:Kirk-Othmer Encycop.Chemical Technology, 5thEd,16,, 538-594 (2006)
• Book:“Advances in Green Chemistry: Chem. Synth. Using MW Irradiation” AstraZeneca Res. Foundn, India (2002)
• Clay and Clay-supported Reagents in Organic Syntheses, Tetrahedron Report # 598, Vol. 58, 1235-55 (2002)
• Solvent-free Organic Syntheses Using Supported Reagents and Microwaves: Green Chemistry, 43-55 (1999)
CLEAVAGE–PROTECTION/DEPROTECTION:
• Chemoselective Cbz-Protection of Amine using Silica-Sulfuric Acid at Room Temp.: Tetrahedron Lett., 48, 8170 (2007)
• Synthesis of Thio-ketones, Lactones, Amides & Thionoesters–Lawesson's reagent: Organic Letters, 1, 697 (1999)
• Deoximation to Carbonyls Using Ammonium Persulfate/Silica: Tetrahedron Lett., 38, 5427 (1997)
• Dethioacetalization to Carbonyls-Clayfen[Iron(III) nitrate/clay]: Tetrahedron Lett., 38, 2623 (1997)
• Deacylation of Esters-Alumina:Perkin Trans.-1, 999, (1993);Desilylation (Alcohols)-Alumina: Tet. Lett. 34, 3029 (1993)
CONDENSATION–CYCLIZATION-DEHYDRATION:
• Mixing with MW-Solvent-free & Catalyst-free Synth. of Pyrazoles and Diazepines: Tetrahedron Lett., 54, 1538 (2013)
• Cat.-free One-pot Synth. of - & -Hydroxy Sulfides from Iodonium Salts with MW: Eurp. J. Org. Chem., 6852 (2012)
• Ring-fused Aminals: Catalyst & Solvent-free MW-amination of N-Heterocycles: Tetrahedron Lett., 49, 7165 (2008)
• Michael Addition Reaction of -Unsaturated Carbonyl Compounds by PEG: Tetrahedron Lett., 49, 6974 (2008)
• MW Solvent-free Ritter reaction-Synthesis of Amides from Alcohols and Nitriles: Tetrahedron Lett., 49, 2661 (2008)
• MW One-pot Solvent-free Synthesis of 1,3,4-Oxadiazoles and 1,3,4-Thiadiazoles: Tetrahedron Lett., 49, 879 (2008)
• Synth of Pyrazoles and Diazepines in Aqueous Medium-Polystyrene Sulfonic Acid: Tetrahedron Lett., 49, 397 (2008)
• Synthesis of Ureas, Cyclic Ureas & Urethanes from Diamines in presence of ZnO: Tetrahedron Lett., 45, 7205 (2004)
• Propargylamine via-Cu-Cat. Coupling of Aldehyde, Alkyne & Amines: QSAR & Combinatorial Science, 23, 891 (2004)
• Catalyst-free & Solvent-free Synth. Heterocyclic Hydrazones: Chem. Commun., 1716 (2001); Green Chem., 4, 35 (2002)
• 3-Compont. Ugi Rxn.–Imidazo[1,2-a]annulated Pyridines, Pyrazines & Pyrimidines:Tetrahedron Lett., 40, 7665 (1999)
• Biginelli Rxn.– Synth of 4-Ph-3,4-dihydropyrimidin-2-ones: Synthesis, 1799 (1999); Tetrahedron Lett., 48, 7343 (2007)
• Synthesis of N-Sulfonylamines Using Clay, Carbonate and Orthoformate:Tetrahedron Lett., 40, 4951 (1999)
• Solid State Synthesis of 2-Aroylbenzofurans, Thiazoles etc. J. Chem. Soc. Perkin Trans-1, 4093 (1998)
• One-Pot Synthesis of 2-Amino Substituted Isoflav-3-enes from Enamines: J. Org. Chem.63, 8038, (1998)
• Synthesis of Nitroalkenes from Carbonyl Compounds (Henry Reaction): Tetrahedron Lett., 38, 5131 (1997)
• Synthesis of 2-Ph-1,2,3,4-Tetrahydro-4-Quinolones from 2'-Aminochalcones–Clay: Synlett, 857 (1997)
OXIDATION:
• Ferrate: Greener Oxidants with Multimodal Action in Water Treatment Technologies: Acc. Chem. Res., 48,182 (2015).
• Oxidation of Styrenes with SiO2-Supported Iron Oxide Nanocatalysts in water: Adv. Synth. Cat., 354, 1707 (2012).
• Process Intensification-Oxidation Benzyl Alcohol-Continuous Isothermal Reactor-MW: Green Chem., 8, 29 (2006)
• Oxidation of Dihydropyridines to Pyridines with Sulfur: J. Chem. Soc. Perkin Trans-1, 1755 (1999)
• General Oxidation Reaction-Claycop [Copper(II) nitrate/Clay]/H2O2: Tetrahedron Lett.,39, 1307 (1998)
• Oxidn. of Sulfides & Alcohols by [PhI(OAc)2]/Al2O3: J. Chem. Res. (S), 120 (1998); Tetrahedron Lett., 38, 7029 (1997)
• Oxidation of Sulfides to Sulfoxides & Sulfones–Wet NaIO4/SiO2: Tetrahedron Lett., 38, 6525 (1997)
• Oxidation of Alcohols–Clayfen: Tetrahedron Lett., 38, 2043 (1997); using Fe(NO3)3: Tetrahedron Lett., 48, 8839 (2007)
REDUCTION:
• Revisiting Meerwien-Ponndorf-Verley Redn.-Sustainable Transfer Hydrogenation: Green Chem., 11, 1313 (2009)
_______________________________________________________________________________
Cincinnati, Ohio, USA. Ph: (513) 487-2701; E-mail: Varma.Rajender@epa.gov;
rajvarma@hotmail.com
Web: http://www.epa.gov/nrmrl/std/organic_reactions.html
P.T.O.
• Hydrodechlorination of Chlorinated Benzenes in Continuous MW reactor: Green Chem., 6, 295 (2004)
• Reduction of Nitrocompounds to Amines on Alumina-supported Hydrazine: Tetrahedron Lett. 42, 5347 (2001)
• Sec- & Tert-Amines via Reductive Amination of Carbonyls-NaBH4/Wet Clay: Tetrahedron, 54, 6293 (1998)
• Redn. Carbonyls—NaBH4/Al2O3:Tetrahedron Lett., 38, 4337 (1997); Cannizzaro Rxn:Tetrahedron Lett. 39, 8437 (1998)
IONIC LIQUIDS:
• Indate(III) Ionic Liquids-Coupling of CO2 with Epoxides-Cyclic Carbonate Formation, J. Org. Chem.,70, 7882 (2005)
• Indium IL-Tetrahydropyranyl,Tetrahedron Lett., 46, 1467, 2005; Gallium IL-Acetals, Tetrahedron Lett., 46, 7447, 2005
• Aldol- & Mannich-type Reactions via in situ Olefin Migration in Ionic Liquids, Organic Letters, 5, 657 (2003).
• Solvent-free Route to Ionic Liquids Using MW & Tetrahydropyranylation, Chem. Commun., 643 (2001); 342 (2002)
• MW Solvent-free Prep of IL’s:Pure Appl. Chem., 73, 1309 (2001);Sonochemical Prepn. of IL’s: Org. Lett. 4, 3161 (2002)
---Related Environmentally Benign Organic Reactions Using Alternate Reaction Media(water), Clay, or Zeolites --• Aqueous Ring Closing Metathesis & Hydrosilylation with Grubbs 2 nd Gen. Ru Catalyst: J. Org. Chem., 73, 7417 (2008)
• Pd-N-Heterocyclic Carbene (NHC) Organic Silica: Appls. in C-C Coupling Reactions: Tetrahedron 64, 4637 (2008)
• Tandem Bis-Aldol Reaction of Ketones: MW Synth. of 1,3-Dioxanes in Aqueous Medium:J. Org. Chem.72,7420 (2007)
• Nuc.Subst.Rxns-MW Aqueous Media Synthesis Alkyl Azides, Thiocyanates and Sulfones:J. Org. Chem.71,6697 (2006)
• MW Synthesis Pyrazole, Pyrazolidine etc. using Hydrazine: Tet .Lett., 46, 6011 (2005); J. Org. Chem.71, 135 (2006)
• Synthesis of N-aryl Azacycloalkanes, MW-assisted N-heterocyclization of Anilines: Organic Letters, 7, 2409 (2005)
• Feature: Environmentally Friendlier Transformations on Mineral Supports, J. Mat.Chem., 12, 3199 (2002).
• Microwave-Accelerated Suzuki Cross-coupling Reaction in PEG: Green Chemistry, 3, 146 (2001)
• Urea-H2O2: Solid State Oxidns for Nitriles, Sulfides & N-Heterocycles & (Dakin Reaction) Organic Lett., 1, 189 (1999)
• Pd Intercalated Clay for Heck Rxn: Tetrahedron Lett., 40, 2075(1999); Suzuki Rxn: Tetrahedron Lett., 40, 439(1999).
• Sulfides via Ce-exchan. NaY Catalyst: Chem. Commun., 621 (1997); Sulfoxides-Urea H2O2 Chem. Commun., 471 (1997)
Ultrasound-promoted Reactions:
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Mag. Nano Pd-Heck-type Arylation of Alkenes with diaryliodonium Salts in Water/PEG: Green Chem, 14, 2133 (2012)
Cu-Catalyzed Ultrasound-Expedited N-Arylation of Sulfoximines: Adv. Synth. Cat., 354, 986-990 (2012).
Ultrasound-expedited Epoxidation of Olefins over Hydrotalcites and H 2O2, Synth. Commun., 33, 2017 (2003)
Can Ultrasound Substitute for PTC? Catalysis & Sonic Nucl. Subst. Rxn-Azides: J. Mol. Cat. A. Chem., 149,153 (1999)
Ultrasound-accelerated Aqueous KMnO4 Oxidn. of Styrenes to 1,2-Diols: Tetrahedron Lett. 39, 7463 (1998)
Nanomaterials via Novel ‘Greener’ Routes and their Application as Nano-Catalysts:
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Nano TiO2 Films: Application in Remediation of Organic Pollutants: Coordination Chem. Rev., 306, 43-64 (2016).
Magnetically Retrievable Catalysts for Asymmetric Synthesis: Coordination Chem. Rev., 287, 137-156 (2015).
Fate of Engineered Nanoparticles – Implications in the Environment: Coordination Chem. Rev., 287, 64-78 (2015).
Journey on Greener Pathways-Perspective article for 15 Years GC Celebration: Green Chem., 16, 2027-2041 (2014)
Separation & Measurement of Ag Nanoparticles with Magnetic Particles: Sci. Total Env.472, 316 (2014)
Ag Surfaces H2O Disinfection:Curr.Opin.Chem.Eng.3,25(2014);Microcystin removal-TiO2 Chem.Comm.,49,10118 (2013)
Book: Sustainable Preparation of Metal Nanoparticles: Methods & Applications-RSC Green Chemistry Series (2013)
Nano-Magnetite Supports in the Development of Sustainable Methodologies. Chem Soc. Rev. 42, 3317 (2013)
Controlled Ag Nanowires-Glycerol & MW:Chem.Commun.,49,692(2013);(Au,Pt,Pd): ACS Sus.Chem.Eng.,1, 810 (2013)
Beet Juice-Synth. Plasmonic AgCl/Ag:ChemSusChem, 5, 2435(2012);Nanometals(Pd,Pt,Au,Ag):RSC Adv.2,10283 (2012)
Magnetic Nano Supp. Glutathione-Homocoupling of Boronic Acids in water: Green Chem, 12, 1540 (2010)-Cover Page
Synth. Charact. & Biocompatibility of “Green” Ag Nanoparticles Using Tea Polyphenols: Nanoscale, 2, 763 (2010)
In Vitro Biocompatibility of NZVI, Fe Synthesized Using Tea Polyphenols: Green Chem., 12, 114 (2010)-Hot Paper.
Rags to Riches Story: Metal Nanoparticles from Waste-Using Grape Pomace Extract, ChemSusChem, 2, 1041 (2009)
Degradation Bromothymol Blue with Zerovalent Iron Generated by Tea Polyphenols: J. Mater. Chem, 19, 8671 (2009)
Magnetic Nano Supp. Glutathione-Sustain. Organocatalyst: Chem Commun.1837 (2009); Tetrahedron, 66, 1091 (2010)
Self-Assembly of Metal Oxides in to 3-dimensional Nanostructures: Synth. & Appl. Catalysis: ACS Nano, 3,728 (2009)
Nano Mag Recov. Ru OH: Hydration of Nitriles to Amides in water: Chemistry: A Europ. Journal, 15, 1582 (2009).
Synth. & Functionalization of Magnetic Nanoferrites via MW Hydrothermal: J. Phys. Chem.C, 112, 18399 (2008)
Green Synthesis of Ag & Pd Nanoparticles at Room Temp. Using Coffee & Tea Extract: Green Chem., 10, 859 (2008)
Synth of Core (Fe, Cu)-Shell (Au, Pt, Pd and Ag) Nanocrystals- Aqueous Vit. C: Crystal Growth Design, 7, 2582 (2007)
MW Synth of Carboxymethyl Cellulose/Metal Biodegradable Nanocomposites, Biomacromolecules, 8, 2762 (2007)
Bulk Synth. Noble Nanocrystals with Microwaves & Aqueous Sugar Solutions. Crystal Growth & Design, 7, 686 (2007)
Au & Pt Nanomaterials Using Vit B2: Density-assisted assembly of Spheres, Wires & Rods: Green Chem., 8, 516 2006)
Mechanochemical Solvent-Free Mixing (grinding):
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PhI(OH)OTs-Synth of -Tosyl. -Ketosulfones Tet. Lett., 47, 8239 (2006); of -Ketosulfones: Tet Lett. 47, 4197 (2006)
Solvent-free Synth of Aryl-4-Me-1,2,4-Triazolo[4,3-a]Quinoxalines Using PhI(OAc)2: Green Chem.,6, 156 (2004)
_______________________________________________________________________________
Cincinnati, Ohio, USA. Ph: (513) 487-2701; E-mail: Varma.Rajender@epa.gov;
rajvarma@hotmail.com
Web: http://www.epa.gov/nrmrl/std/organic_reactions.html
P.T.O.