Centro de Quı́mica-Fı́sica Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Quı́mica e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Quı́mica, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal

More sustainable approaches for the synthesis of N-based heterocycles.

Biopolymers such as DNA store information in their chains using controlled sequences of monomers. Here we describe a non-natural information-containing macromolecule that can store and retrieve digital information. Monodisperse sequence-encoded poly(alkoxyamine amide)s were synthesized using an iterative strategy employing two chemoselective steps: the reaction of a primary amine with an acid anhydride and the radical coupling of a carbon-centred radical with a nitroxide. A binary code was implemented in the polymer chains using three monomers: one nitroxide spacer and two interchangeable anhydrides defined as 0-bit and 1-bit. This methodology allows encryption of any desired sequence in the chains. Moreover, the formed sequences are easy to decode using tandem mass spectrometry. Indeed, these polymers follow predictable fragmentation pathways that can be easily deciphered. Moreover, poly(alkoxyamine amide) s are thermolabile. Thus, the digital information encrypted in the chains can be erased by heating the polymers in the solid state or in solution.

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Design and synthesis of digitally encoded polymers that can be decoded and erased.

Hydrosoluble, UV-crosslinkable and injectable chitosan for patterned cell-laden microgel and rapid transdermal curing hydrogel in vivo.

1. A Fifty Year Perspective on Chemistry in Water (R. Breslow). 1.1 Enzyme mimics and models. 1.1.1 Thiamine. 1.1.2 Cyclodextrins. 1.1.3 Cyclodextrins with bound metal ions. 1.1.4 Cyclodextrin dimers. 1.1.5 Ribonuclease mimics. 1.1.6 Transaminase mimics. 1.1.7 Cytochrome P-450 mimics. 1.2 Reactions in Water Promoted by Hydrophobic Binding of Small Molecules. 1.2.1 Diels-Alder reactions. 1.2.2 The benzoin condensation. 1.2.3 Atom transfer reactions. 1.3 Quantitative Antihydrophobic Effects in Water, and the Geometries of Transition States. 1.4 The Importance of Water as a Reaction Solvent. 2. Structure and Properties of Water (J. B. F. N. Engberts). 2.1 Water. The molecule and the liquid. 2.1.1 The single water molecule. 2.1.2 Liquid water. 2.2 Properties of water. 2.2.1 Solvent properties and parameters. 2.2.2 Thermodynamics of hydration. 2.2.3 Hydrophobic interactions. 2.3 Kinetic solvent effects in aqueous solutions. 3. Acid Catalysis in Water (C. Ogawa and S. Kobayashi). 3.1 Homogeneous catalysis. 3.1.1 Bronsted acid catalysis. 3.1.2 Lewis acid catalysis. 3.1.3 Asymmetric catalysis. 3.2 Heterogeneous catalysis. 3.2.1 Polymer-supported Bronsted catalysis. 3.2.2 Polymer-supported metal catalysis. 3.3 Micellar catalysis. 3.3.1 LASC (Lewis acid-surfactant combined catalyst). 3.3.2 BASC (Bronsted acid-surfactant combined-catalyst). 3.4 Conclusion. 4. Metal-Mediated C-C Bond Formations in Aqueous Media (C-J. Li). 4.1 Reactivity of organometallic compounds with water. 4.1.1 Carbon-metal bonding. 4.1.2 Carbon-metal hydrolysis. 4.1.3 Carbon-metal reactions. 4.1.4 C-C bond formations via carbon-metal reactions in water. 4.2 Allylation of carbonyls and imines. 4.2.1 Allylation of carbonyl compounds. 4.2.2 Allylation of imines and related compounds. 4.3 Propargylation/allenylation of carbonyls, imines and related compounds. 4.4 Metal-mediated benzylation of carbonyls and imines. 4.5 Arylation and vinylation of carbonyls and imines. 4.5.1 Arylation and vinylation of aldehydes. 4.5.2 Arylation and vinylation of imines. 4.6 Alkynylation of carbonyls, imines, and related compounds. 4.6.1 Alkynylation of aldehyde. 4.6.2 Alkynylation of imines and related compunds. 4.6.3 Asymmetric alkynylation. 4.7 Metal-mediated aldol and Reformatsky-type reactions. 4.8 Metal-mediated alkylation of carbonyls and imines. 4.8.1 Alkylation of carbonyls. 4.8.2 Alkylation of imines. 4.9 Metal-mediated conjugate addition reactions. 4.9.1 Addition of alkyl groups. 4.9.2 Addition of vinyl and aryl groups. 4.9.3 Addition of alkynes. 4.10 Metal-mediated coupling reactions. 4.10.1 Pinacol coupling. 4.10.2 Other reductive couplings. 4.10.3 Cross-Dehydrogenative-Coupling. 4.11 Conclusions. 4.12 Acknowledgements. 5. Pericyclic Reactions in Aqueous Media (F. Fringuelli, O. Piermatti, F. Pizzo, L. Vaccaro). 5.1 Diels-Alder Cycloaddition Reactions. 5.1.1 Carbo Diels-Alder Reactions. 5.1.2 Biocatalyzed Carbo Diels-Alder Reactions. 5.1.3 Hetero Diels-Alder Reactions. 5.1.4 The Role of Water. 5.2 1,3-Dipolar Cycloaddition Reactions. 5.2.1 Pyrrole and Pyrrolidine-Ring Formation. 5.2.2 Isoxazole and Hydroderivatives-Ring Formation. 5.2.3 Pyrazole and Pyrazoline-Ring Formation. 5.2.4 Triazole and Triazoline-Ring Formation. 5.2.5 Tetrazole-Ring Formation. 5.3 [2+2] Photo-Cycloaddition Reactions. 5.4 Claisen Rearrangement Reactions. 6. Catalyzed Reductions in Aqueous Media (T. V. RajanBabu and S. Shin). 6.1. Special features of hydrogenation in water mediated by organometallic catalysts. 6.2. Water-soluble complexes for aqueous hydrogenation. 6.2.1. Sulfonated phosphine and other ligands. 6.2.2. Nitrogen-containing phosphine ligands. 6.2.3. Hydroxyphosphines and other oxygen-containing ligands. 6.3. Hydrogenation of C=C bond. 6.3.1. Reductions of dehydroamino acid and acrylic acid derivatives. 6.4. Hydrogenation of C=O bond. 6.4.1. Chemoselectivity of C=C vs. C=O bonds. 6.5. Asymmetric reduction of C=O bond in water. 6.5.1. Asymmetric hydrogenation of C=O bond in water. 6.5.2. Asymmetric transfer hydrogenation of C=O bond in water. 6.5.3. Hydrogenation of C=N bond. 6.6. Miscellaneous reductions. Reduction of epoxides, halides and carbon dioxide. 6.7. Summary and outlook. . 7. Oxidations (Roger A. Sheldon). 7.1 Water-soluble ligands. 7.2 Oxidations catalyzed by metalloporphyrins and metallophthalocyanines. 7.3 Epoxidation and dihydroxylation of olefins in aqueous media. 7.4 Alcohol oxidations in aqueous media. 7.5 Aldehyde and ketone oxidations in water. 7.6 Sulfoxidations in water. 7.7 Concluding remarks. . 8. Nucleophilic Additions and Substitutions in Water (D. Sinou). 8.1 Nucleophilic Additions. 8.1.1 The Aldol Reaction. 8.1.2 Michael Addition. 8.1.3 Mannich-Type Reaction. 8.2 Nucleophilic Substitution. 8.2.1 Ring-opening nucleophilic substitution. 8.2.2 Alkylation Reactions. 8.2.3 Other types of substitutions. 8.3 Conclusion. 9. Reactions in Nearcritical Water (C.L. Liotta, J.P. Hallett, P. Pollet, C.A. Eckert). 9.1 Characterization of Nearcritical Water. 9.1.1 Physical and Thermodynamic Properties of Nearcritical Water. 9.1.2 Solvatochromic Characterization of Nearcritical Water. 9.2 Reactions in Nearcritical Water. 9.2.1 Hydrolysis of Ester and Ether. 9.2.2 Hydrolysis of Nitriles. 9.2.3 Hydration of -pinene. 9.2.4 Elimination Reactions. 9.2.5 Friedel-Crafts Alkylation Reactions. 9.2.6 Friedel-Crafts Acylation Reactions. 9.2.7 Condensation Reactions. 9.2.8 Rearrangements. 9.2.9 Hydrogen/Deuterium Exchange. 9.2.10 General Acid Base Reactions. 9.3 Reactions in High Temperature Water Enriched with CO2. 9.4 Limitations & Safety. 9.5 Conclusion. 10. Biocatalysis in Water (K. Nakamura, T. Matsuda). 10.1 Basic aspects of biocatalysis. 10.1.1 Reaction classification. 10.1.2 Kinetics of enzymatic reactions. 10.1.3 Reaction mechanism. 10.1.4 Selectivities. 10.1.5 Experimental conditions. 10.2 Reduction. 10.2.1 Stereochemistry of hydride transfer. 10.2.2 Baker's yeast catalyzed reaction. 10.2.3 Overexpression of key reductases from baker's yeast in E. coli. 10.2.4 Asymmetric reduction by Geotrichum candidum. 10.2.5 Hydrogen sources. 10.2.6 Reduction of carbon-carbon double bonds. 10.2.7 Reduction of hydroperoxides. 10.2.8 Reduction of sulfoxides. 10.3 Oxidation. 10.3.1 Oxidation of alcohols. 10.3.2 Hydroxylation. 10.3.3 Baeyer-Villiger oxidations. 10.3.4 Oxidation of sulfur compounds. 10.3.5 Oxidative polymerization. 10.4 Hydrolysis of esters. 10.4.1 E-value. 10.4.2 Synthesis of chiral compounds by enzymatic hydrolysis of esters. 10.4.3 Hydrolysis of sterically hindered esters. 10.4.4 Hydrolysis of esters with fluorine functionalities. 10.4.5 Methods of controlling reactivity and enantioselectivity. 10.4.6 Control of reactivity and enantioselectivity by genetic engineering. 10.4.7 Hollow-Fiber membrane reactor for lipase catalyzed hydrolysis: synthesis of Diltiazem. 10.4.8 Lipase catalyzed optical resolution coupled with in situ inversion: synthesis of Prallethrin (pyrethroid) etc. 10.4.9 Recognition of fluorinated functionalities from unfluorinated group: H vs. F. 10.4.10 P-chiral and S-chiral compounds. 10.5 Other types of hydrolysis, dehydration and halogenation. 10.5.1 Hydrolysis of expoxides. 10.5.2 Hydrolysis of amide and nitrile. 10.5.3 Dehydration in water for the synthesis of nitriles. 10.5.4 Desulfonation. 10.5.5 Direct glycosylation. 10.5.6 Dehalogenation. 10.5.7 Fluorination. 10.6 C-C bond formations. 10.6.1 Aldol reactions. 10.6.2 Cyanohydrin synthesis. 10.6.3 Carboxylations. 10.7 Dynamic kinetic resolution. 10.7.1 Dynamic kinetic resolution of racemic ketones through asymmetric reduction. 10.7.2 Dynamic kinetic resolution using hydrolytic enzymes. 10.7.3 Deracemization. 10.8 Conclusion. 11. Chemistry 'On Water' - Organic Synthesis in Aqueous Suspension (S. Narayan, V. V. Fokin, K. B. Sharpless). 11.1 Background. 11.2 The Unique Reactivity of Azodicarboxylates on Water. 11.3 Other Examples from Our Work. 11.4 Applications of the 'On Water' Method. 11.5 Perspective and Conclusion. 12. Water as a Reaction Solvent - an Industry Perspective (Ernst Wiebus, Boy Cornils). 12.1 Hydroformylation as the Master Development. 12.1.1 General. 12.1.2 Immobilization with the Help of Liquid Supports. 12.1.3 Principles. 12.2 Examples of Aqueous Phase Catalyses. 12.2.1 Hydroformylation (Ruhrchemie/Rhone-Poulenc[RCH/RP] process). 12.2.2 Other Industrially Used Aqueous-biphasic Processes. 12.2.3 Short Overview of other (Lab scale) Reactions. 12.3 The "Aqueous" Recycle and Recovery of Biphasic Catalysts. 12.3.1 Recycle. 12.3.2 Recovery. 12.4 Economics of the Process. 12.5 Environmental Aspects. 12.6 Concluding remarks.

Organic reactions in water : principles, strategies and applications

We present the results of quantum chemical calculations of the electronic properties of the anionic form of the green fluorescent protein chromophore in the gas phase. The vertical detachment energy of the chromophore is found to be 2.4−2.5 eV, which is below the strongly absorbing ππ* state at 2.6 eV. The vertical excitation of the lowest triplet state is around 1.9 eV, which is below the photodetachment continuum. Thus, the lowest bright singlet state is a resonance state embedded in the photodetachment continuum, whereas the lowest triplet state is a regular bound state. Based on our estimation of the vertical detachment energy, we attribute a minor feature in the action spectrum as due to the photodetachment transition. The benchmark results for the bright ππ* state demonstrated that the scaled opposite-spin method yields vertical excitation within 0.1 eV (20 nm) from the experimental maximum at 2.59 eV (479 nm). We also report estimations of the vertical excitation energy obtained with the equation-o...

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Quantum Chemical Benchmark Studies of the Electronic Properties of the Green Fluorescent Protein Chromophore. 1. Electronically Excited and Ionized States of the Anionic Chromophore in the Gas Phase

Chemoselective Acylation of Amines in Aqueous Media

Amines in the form of amine hydrochlorides are efficiently acylated with anhydrides in an aqueous medium on addition of NaHCO3. Both cyclic and acyclic anhydrides react with equal ease with an amine and amines of various stereo-electronic factors react with the same rates with an anhydride. No chromatographic separation is needed for isolation of the acylated product. Reactions in aqueous medium, innocuous by-products and chemoselective acylation of amines in the presence of phenols and thiols have been achieved with high selectivity.

Mild and eco-friendly chemoselective acylation of amines in aqueous medium

Photovoltaic effect in single-layer organic solar cell devices fabricated with two new imidazolin-5-one molecules

A short CO⋯C intermolecular contact and a weak C–H⋯π hydrogen bonding hold the molecules of (4Z)-4-(4-methoxybenzylidene)-1,2-diphenyl-1,4-dihydro-5H-imidazolin-5-one in a zigzag steps type of molecular assembly.

Gitalee Bhattacharjya

Papers

Chemoselective Acylation of Amines in Aqueous Media

Mild and eco-friendly chemoselective acylation of amines in aqueous medium

Photovoltaic effect in single-layer organic solar cell devices fabricated with two new imidazolin-5-one molecules

Short CO⋯C intermolecular contacts for molecular assembly

C H⋯O interactions are favoured in the crystal structures of imidazolin-5-ones