Comprehension of the basic concepts for the design of systems for CO2 adsorption is imperative for increasing interest in technology for CO2 capture from the effluents. The efficacy of 20 naturally occurring amino acids (AAs) is demonstrated as the most potent CO2 capturing agents in the process of chemical absorption and physisorption through a systematic computational study using highly parametrized M05-2X/6-311+G(d,p) method. The ability of AAs to bind CO2 both in the noncovalent and covalent fashion and presence of multiple adsorption sites with varying magnitude of binding strengths in all 20 AAs makes them as most promising materials in the process of physisorption. The binding energies (BEs) estimating the strength of noncovalent interaction of AAs and CO2 are calculated and results are interpreted in terms of the nature and strength of the various types of cooperative interactions which are present. The study underlines the possibility to engineer the porous solid materials with extended networks by judiciously employing AA chains as linkers which can substantially augment their efficacy. Results show that a significant increase in the CO2···AA affinity is achieved in the case of AAs with polar neutral side chains. Furthermore, the study proposes AAs as effective alternatives to alkanolamines in chemical dissolution of CO2.

C 3 symmetric chiral trimethylsumanene was enantioselectively synthesized through Pd-catalyzed syn-selective cyclotrimerization of an enantiomerically pure iodonorbornenone, ring-opening/closing olefin metathesis, and oxidative aromatization where the sp 3 stereogenic center was transmitted to the bowl chirality. Chiral HPLC analysis/resolution of the derivatives were also achieved. Based on theoretical calculations, the columnar crystal packing structure of sumanene and trimethylsumanene was interpreted as due to attractive electrostatic or CH³ interaction. According to the experimental and theoretical studies, the bowl depth and inversion energy were found to increase on methylation for sumanene in contrast to corannulene. Dissimilarities of the effect of methylation on the bowl structure and inversion energy of sumanene and corannulene were ascribed to differences in steric repulsion. A double-well potential model was fitted to the bowl structureinversion energy correlation of substituted sumanenes, with a small deviation. The effects of various substituents on the sumanene structure and bowl-inversion energy were analyzed by density functional theory calculations, and it was shown that the bowl rigidity is controlled by a combination of electronic and steric effects of the substituents. The electron conductivity of trimethylsumanene was investigated by time-resolved microwave conductivity method, compared with that of sumanene.In the wake of the discovery of fullerene, the chemical and physical properties of buckybowls have attracted a great deal of interest because of their unique bowl-shaped ³-conjugated structure. 13 The science of buckybowls has grown as a result of the development of practical routes for the synthesis of compounds such as sumanene (1) 4 and corannulene (2) have also been studied. With this background knowledge, we studied five aspects of C 3 symmetric trimethylsumanene (3), as listed below. Direct Selective Synthesis of C 3 Symmetric Substituted Sumanenes. One of the major difficulties in studying the properties of sumanene (1) is that of selective synthesis of its derivatives. Because sumanene is C 3v symmetric, the selective synthesis of C 3 symmetric trisubstituted derivatives through functionalization at either methylene or benzene is difficult to achieve. Functionalization of the parent compound 1 results in mixtures of regioisomers, with the desired C 3 symmetric derivatives as minor products that are difficult to separate. 6c,6i Because of the importance of C 3 symmetric trisubstituted derivatives for studies on the physical properties of sumanene (1) and its derivatives or for further transformation into ³-conjugated derivatives, functionalized sumanenes have to be

Two new heteroleptic ruthenium(II) photosensitizers that contains 2,2';6,2''-terpyridine with extended π-conjugation with donor groups, a 4,4'-dicarboxylic acid-2,2'-bipyridine anchoring ligand and a thiocyanate ligand have been designed, synthesized and fully characterized by CHN, mass spectrometry, UV-vis and fluorescence spectroscopies and cyclic voltammetry. The new sensitizers have either 3,5-di-tert-butyl phenyl (m-BL-5) or triphenylamine (m-BL-6) groups, where the molar extinction coefficient of both the sensitizers is higher than the analogous ruthenium dyes. Both the sensitizers were tested in dye-sensitized solar cells using two different redox electrolytes.

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