@article { ISI:000233948800019, title = {Nucleobases in molecular recognition: molecular adducts of adenine and cytosine with COOH functional groups}, journal = {Angewandte Chemie International Edition}, volume = {44}, number = {47}, year = {2005}, month = {NOV}, pages = {7752-7757}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, keywords = {carboxylic acids, hydrogen bonds, molecular recognition, nucleobases, supramolecular chemistry}, issn = {1433-7851}, doi = {10.1002/anie.200502434}, author = {Perumal, Sathiamurthi and Suresh, E. and Pedireddi, V. R.} } @article {31}, title = {Metal-induced reductive ring opening of 1,2,4,5-tetrazines: Three resulting coordination alternatives, including the new non-innocent 1,2-diiminohydrazido(2-) bridging ligand system}, journal = {Inorganic Chemistry}, volume = {45}, number = {3}, year = {2006}, month = {FEB }, pages = {1316-1325}, publisher = {WILEY-V C H VERLAG GMBH}, type = {Article}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

{Reaction of 3,6-diaryl-1,2,4,5-tetrazines (aryl = R = phenyl, 2-furyl or 2-thienyl) with 2 equiv of Ru(acac)(2)(CH3-CN)(2) results in reductive tetrazine ring opening to yield diruthenium complexes [

}, keywords = {crystal engineering, hydrogen bonds, molecular, recocynition, Self-assembly, supramolecular chemistry}, issn = {0947-6539}, doi = {10.1021/ic051532p}, author = {Maji, Somnath and Sarkar, B. and Patra, S. and Fiedler, Jan and Mobin, Shaikh M. and Puranik, Vedavati G. and Kaim, Wolfgang and Lahiri, Goutam Kumar} } @article { ISI:000258683600017, title = {pK(a)-Directed host-guest assemblies: rational analysis of molecular adducts of 2,4-diamino-6-methyl-1,3,5-triazine with various aliphatic dicarboxylic acids}, journal = {Chemistry-A European Journal}, volume = {14}, number = {23}, year = {2008}, month = {JUL}, pages = {6967-6977}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

Molecular adducts of 2,4-diamino-6-methyl-1,3,5-triazine (1) have been prepared with various aliphatic dicarboxylic acids. The molecular complexes (1a-1i) thus formed by co-crystallizing 1 with oxalic, malonic, succinic, fumaric, acetylene dicarboxylic, glutaric, thiodiglycolic, diglycolic, and adipic acids have been found to give two types of host-guest assemblies that have voids or channels in a three-dimensional arrangement. The different types of host-guest arrangement appear to result from differences in the acidity of the dicarboxylic acids, that is, acids with pK(a) \< 3.0 give host networks that consist of 1 and the corresponding acid with water or solvent molecules of crystallization present as guests, whereas acids with pK(a) \> 3.0 exist as guests in voids in a host network formed by 1. The former arrangement is observed in adducts 1a, 1b, 1c, and 1h and the latter arrangement is found in adducts 1c, 1d, 1f, 1g and 1i.

}, keywords = {dicarboxylic acids, host-guest systems, hydrogen bonds, molecular recognition, supramolecular chemistry}, issn = {0947-6539}, doi = {10.1002/chem.200800649}, author = {Delori, Amit and Suresh, Eringathodi and Pedireddi, V. R.} } @article { ISI:000255798800008, title = {Van der waals and polar intermolecular contact distances: quantifying supramolecular synthons}, journal = {Chemistry-an Asian Journal}, volume = {3}, number = {5}, year = {2008}, month = {APR}, pages = {868-880}, publisher = {WILEY-V C H VERLAG GMBH}, type = {Article}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

Crystal structures are viewed as being determined by ranges and constraints on interatomic contact distances between neighboring molecules. These distances are considered to arise from environment-dependent atomic sizes, that is, larger sizes for isotropic, van der Waals type contacts and smaller sizes for more-polar, possibly ionic contacts. Although the idea of different, or anisotropic, radii for atoms is not new, we developed a method of obtaining atomic sizes that is based on a theoretical framework. Using different atomic sizes for the same atom in different environments, we were able to rationalize some structural observations and anomalies. For example, benzene with the Pbca structure may be described in terms of two types of C center dot center dot center dot H interactions: a longer contact largely of the van der Waals type, and a shorter, structure-determining type (C delta-center dot center dot center dot H delta+), which we term {\textquoteleft}{\textquoteleft}n-polar{\textquoteright}{\textquoteright}. Our approach is illustrated with three examples: 1) the equivalence in crystal packing of fluorobenzene, benzonitrile, pyridine N-oxide, and pyridine/HF 1:1 molecular complex, all of which take the not-so-common tetragonal P4(1)2(1)2 space group and are practically isomorphous; 2) the similarity of the Pa3 acetylene and Pbca benzene crystal structures; and 3) the equivalence between an increase in pressure and an increase in the {\textquoteleft}{\textquoteleft}n-polar{\textquoteright}{\textquoteright} contacts in Pbca benzene; in other words, the equivalence between hydrostatic pressure and chemical pressure. In the context of crystal engineering, we describe a method whereby the topological information conveyed in a supramolecular synthon is recast in a more quantitative manner. A particular synthon, and in turn the crystal structure to which it leads, is viable within small ranges of distances of its constituent atoms, and these distances are determined by chemical factors.

}, keywords = {atomic radii, benzene crystal, engineering, supramolecular chemistry, van der Waals radii}, issn = {1861-4728}, doi = {10.1002/asia.200700343}, author = {Ganguly, Parthasarathy and Desiraju, Gautam R.} } @article { ISI:000316451500010, title = {Easy and multigram-scale synthesis of pillar[5]quinone by the hypervalent iodine oxidation of 1,4-dimethoxypillar[5]arene}, journal = {Synthesis-Stuttgart}, volume = {45}, number = {7}, year = {2013}, month = {APR}, pages = {896-898}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

Pillar[5]quinone (P[5]Q), a potential molecule for anion recognition and supramolecular host-guest chemistry, has not as yet been used for practical purposes, presumably due to the synthetic difficulties in obtaining it in large amounts. Herein, we reveal an easy-to-operate and chromatography-free synthetic strategy that can furnish P[5]Q on a multigram scale; its success relies on the utility of hypervalent iodine, generated in situ from Oxone/ iodobenzene, as an efficient oxidant. Pillar[5]quinone was obtained in multigram quantities by oxidation of 1,4-dimethoxypillar[5]arene with Oxone/iodobenzene and simple purification by crystallization from 1,1,2,2-tetrachloroethane, thus opening up the opportunity to explore the properties of this interesting macrocyclic quinone.

}, keywords = {hypervalent iodine oxidation, macromolecules, pillar-arenes, supramolecular chemistry}, issn = {0039-7881}, doi = {10.1055/s-0032-1318390}, author = {Shivakumar, Kilingaru I. and Sanjayan, Gangadhar J.} } @article { ISI:000321431600027, title = {Proton-conducting supramolecular metallogels from the lowest molecular weight assembler ligand: a quote for simplicity}, journal = {Chemistry-A European Journal}, volume = {19}, number = {29}, year = {2013}, month = {JUL}, pages = {9562-9568}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

Oxalic acid has been proven to be the lowest molecular weight organic ligand able to form robust supramolecular metallogel networks in the presence of metal salts. In particular, two novel multifunctional metallogels were readily prepared at room temperature by simple mixing of stock solutions of Cu-II acetate monohydrate or Cu-II perchlorate hexahydrate and oxalic acid dihydrate. Formation of different polymorphs and unprecedented proton conduction under anhydrous conditions were also demonstrated with some of these materials.

}, keywords = {Copper, low-molecular-weight ligands, metallogels, proton conductivity, supramolecular chemistry}, issn = {0947-6539}, doi = {10.1002/chem.201204542}, author = {Saha, Subhadeep and Schoen, Eva-Maria and Cativiela, Carlos and Diaz, David Diaz and Banerjee, Rahul} }