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Valuable new synthetic intermediates, 4-, 5- or 6-chloromethyl-1H-indole-2-carboxylates, were prepared by the facile elimination of SO2 from 2-ethoxycarbonyl-1H-indole-4-, 5- or 6-methanesulfonic acids, respectively, easily accessible by Fischer-type indolization. [Copyright &y& Elsevier]

Focuses on a study that examined microwave-assisted synthesis of phtalonitriles and phtalocyanines. General procedure for the preparation of phtalonitriles; One-pot procedure of the synthesis of phtalocyanines.

Valuable new synthetic intermediates, 4- or 6-chloromethyl-1H-indole-2-carboxylates, were prepared by the elimination of SO2 from 2-ethoxycarbonyl-1H-indole-4- or 6-methanesulfonic acids, respectively, which are easily accessible by Fischer-type indolization. [Copyright &y& Elsevier]

The first representatives of 1,3-alt-thiacalix[4]arene bis(crown-5 and -6) ethers were synthesized by the cyclocondensation of thiacalix[4]arenes with tetraethylene glycol ditosylate and 1,14-diiodo-3,6,9,12-tetraoxatetradecane, respectively. The complexing abilities of ligands were determined by alkali (Na+, K+, Rb+, Cs+) picrate extraction methods. [Copyright &y& Elsevier]

The first representatives of 1,3-alt-thiacalix[4]mono(crown-5 and -6) ethers were synthesized by the cyclocondensation of 25,27-dialkoxythiacalix[4]arenes with tetraethylene glycol ditosylate and 1,14-diiodo-3,6,9,12-tetraoxatetradecane, respectively. The complexing abilities of ligands were determined by the alkali (Li+, Na+, K+, Rb+, Cs+) picrate extraction method. [Copyright &y& Elsevier]

The acid-base properties of 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium dye were investigated. The reagent exists in a reactive single charged form over a wide range of acidity, from pH 8 to -2.5 H0. The optimum analytical wavelength of the single charged form is 412 nm, where the molar absorptivity is 4.06 x 104 dm³ mol-1 cm-1. Mechanisms of protonation and hydrolysis were discussed. The results suggest the applicability of the dye as an effective analytical reactant. Quantum chemical calculations of the structural and spectral properties of the dye were also carried out. [ABSTRACT FROM AUTHOR]

The chiral monoaza-15-crown-5 type lariat ethers 1 and 2 derived from α-d-glucose and from d-mannitol, respectively, have been applied as phase transfer catalysts in the enantioselective Michael addition of 2-nitropropane to aromatic 3b–c and heteroaromatic 3d–h chalcone analogues. Among the catalysts, the glucose-based 1c with a phosphinoxidobutyl side arm proved to be the most effective, it inducing 34% e.e. for 4b, 59% e.e. for 4c, 80% e.e. for 4d, 64% e.e. for 4e, 17% e.e. for 4f. Catalyst 1a having 3-hydroxypropyl substituent resulted in 81% e.e. for compound 4g. The formation of the (+)-(S)-enantiomer of 4 was preferred using crown ethers 1a–c, while the (−)-(R)-enantiomer was in excess with catalyst 2. The absolute configuration of the Michael adduct 4d was determined by single-crystal X-ray analysis. [Copyright &y& Elsevier]

The reaction of 1-(tri-tert-butylphenyl)phosphole (1) with phosphorus tribromide gave the 3-dibromophosphino intermediate (2) selectively that was useful in the synthesis of phosphonic amides 4, H-phosphinic amide 6 and H-phosphinates 8. A similar transformation of the 1-(triisopropylphenyl)phosphole (9) led to a 2-substitution furnishing phosphonic amides 12 or H-phosphinates 14. The phosphorylated phospholes (4, 6, 8) were tested as ligands of transition metal complexes in hydroformylation. [Copyright &y& Elsevier]