The substitution reaction of pure, silicon doped and germanium doped fullerenes and tetryl were evaluated computationally at two configurations, in this study. For this purpose, all of the studied structures were optimized geometrically and then IR and NBO calculations were performed on them in the temperature range of 300-400 K at 10˚ intervals. The obtained negative values of Gibbs free energ...

The nucleophilic substitution of alkyl fluorides was achieved in the intramolecular reactions with O- and N-nucleophiles. The intramolecular defluorinative cyclization reaction was influenced by the nature of nucleophiles, the size of the ring to be formed, and the comformational rigidity of the precursors. Intermolecular nucleophilic substitution reactions of alkyl fluorides under similar reac...

The role of protein dynamics in the reaction catalyzed by dihydrofolate reductase from the hyperthermophile Thermotoga maritima (TmDHFR) has been examined by enzyme isotope substitution ((15)N, (13)C, (2)H). In contrast to all other enzyme reactions investigated previously, including DHFR from Escherichia coli (EcDHFR), for which isotopic substitution led to decreased reactivity, the rate const...

Recent developments in the chemistry of η3-allylruthenium(IV) complexes are due to their straightforward synthesis resulting from oxidative addition of allylic substrates to a ruthenium(II) center. Subsequent reaction with a nucleophile is the basis of their involvement in the catalytic allylic substitution reaction. We focus here on ruthenium-catalyzed substitution of allylic substrates by C-,...

A green and efficient protocol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives via cyclocondensation of 5,5-dimethyl-1,3-cyclohexanedione and aromatic aldehydes in the presence of catalytic amount of 10-molybdo-2-vanadophosphoric acid under solvent-free conditions has been described. The 10-molybdo-2-vanadophosphoric acid was prepared and characterized by ...

A green and efficient protocol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives via cyclocondensation of 5,5-dimethyl-1,3-cyclohexanedione and aromatic aldehydes in the presence of catalytic amount of 10-molybdo-2-vanadophosphoric acid under solvent-free conditions has been described. The 10-molybdo-2-vanadophosphoric acid was prepared and characterized by ...

In this research work, we report the synthesis of macrocyclic diamides from the reaction of diesters and aliphatic diamines in the presence of caesium carbonate. It has been demonstrated that among the carbonate of alkali metals (Li2CO3, Na2CO3, K2CO3 and CS2CO3), CS2CO3 appear to be the best catalyst for macrocyclization. Diesters with different substitution patterns on the aromatic ring react...

in this research work, we report the synthesis of macrocyclic diamides from the reaction of diesters and aliphatic diamines in the presence of caesium carbonate. it has been demonstrated that among the carbonate of alkali metals (li2co3, na2co3, k2co3 and cs2co3), cs2co3 appear to be the best catalyst for macrocyclization. diesters with different substitution patterns on the aromatic ring react...

Synlett 2002, No. 12, Print: 02 12 2002. Art Id.1437-2096,E;2002,0,12,1954,1965,ftx,en;A30202ST.pdf. © Georg Thieme Verlag Stuttgart · New York ISSN 0936-5214 Abstract: Two different synthetic reactions catalyzed by an iridium complex are discussed. The first is allylic alkylation and allylic amination. This reaction proceeds via a -allyl iridium intermediate. The selectivity strongly depends o...