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A boron trihalide mediated alkyne-aldehyde coupling reaction leading to stereodefined 1,3,5-triaryl-l,5- dihalo-1,4-pentadienes is described. The study led to the discovery of a direct substitution of hydroxyl groups by stereodefined alkenyl moieties using alkenylboron dihalides. During the investigation, it was also discovered that, at low temperatures, the reaction of BCI3 with alkynes produces monovinylboron dichioride rather than the reported divinylboron chloride. A modified reaction mechanism for the boron trichloride mediated alkyne-aldehyde coupling reaction is now proposed. The reaction temperature and mode of addition have been found to have dramatic affects on the stereochemistry of the diene products. [ABSTRACT FROM AUTHOR]

A novel boronated aminocyclobutanecarboxylic acid was synthesized for potential use in neutron capture therapy. The synthesis involves the preparation of tosylate 5, which was then converted to an amino acid using Bucherer-Strecker methodology. The molecule was modeled after the unnatural amino acid, 1-aminocyclobutane-1-carboxylic acid, which has shown high uptake in brain tumors. [ABSTRACT FROM AUTHOR]

An alternate reaction mechanism for the boron tribromide mediated deprotection of aryl propargyl ethers based on the isolation of a key boron-containing byproduct is proposed. On the basis of the new mechanistic insight, we discovered that HBBr2·SMe2 can also be used for cleaving aryl propargyl ethers. [ABSTRACT FROM AUTHOR]

The article discusses a study on the structural components of polymers using a topological approach. The study concluded that an integration of Cu(OH)22, NaH2SIP, pyrazine and water can result to an irregular framework composed of copper and coordination compounds. The examination also discovered that the hydrogen-bonded structure is part of a diamondoid component that permeates the metal-pyrazine structure.

The reaction of aryl aldehydes with allylsilanes in the presence of boron trihalides produces haloallylated products. Mechanistic details are presented. [ABSTRACT FROM AUTHOR]

Introduces a convenient approach to 4-substituted 2(5H)-furanones. Effects of solvent and base on the coupling of trans-pentylcyclopropylboronic acid with beta-tetronic acid triflate; Account on the coupling reaction of boronic acids with beta-tetronic acid triflate; Properties of compounds containing 2(5H)-furanone moiety.

Review: 156 refs. [ABSTRACT FROM AUTHOR]

The article focuses on the crystallization of the compound 1-Benzyl-3-(ferrocenylmethyl)imidazolium iodide. The ferrocenyl imidazolium salt is formed from the reaction of 1-benzylimidazole and (ferrocenylmethyl)trimethylammonium iodide in acetonitrile. The compound is a quaternary ammonium salt formed from substituted imidazolium and an iodide anion. The unsubstituted cyclopentadienyl ring shows disorder between two positions.

The title compound, C18H18O5, was prepared by the condensation of 2-hydroxyacetophenone with 3,4,5-trimeth­oxy­benzaldehyde. The trimethoxyphenyl and hydroxy­phen­yl rings of the chalcone system are approximately coplanar. [ABSTRACT FROM AUTHOR]

In the title polymeric complex, [K(C7H5O6S)(H2O)3] n, the anions use their sulfonyl and double-bond carbonyl O atoms to link to four K+ cations in a μ4-bonding mode. The compound has a three-dimensional framework which consists of dinuclear [K2O10] fragments linked by sulfonate and carboxylic O atoms from the sulfosalicylate (ssa−) ligand. In the three-dimensional network, there are different types of channels along the a, b and c axes. In the crystal structure, classical intermolecular O—H...O hydrogen bonds also stabilize the three-dimensional structure. [ABSTRACT FROM AUTHOR]

A novel and convenient carboannulation method for the synthesis of highly substituted naphthylamine derivatives has been developed though a Pd(0)-catalyzed [1,5]-sigmatropic hydrogen shift and cyclization reaction of propargyl esters. [ABSTRACT FROM AUTHOR]

A platinum-catalyzed cycloisomerization of 1 ,6-enyne coupling with the rearrangement chemistry of propargylic ester has been developed. Most probably, under platinum catalysis, propargylic ester undergoes the 1,3-acyloxy migration to afford metal allene intermediate, which is followed by the Diels-Alder-type reaction. 1,3-Acyloxy migration is the key step during the transformation. [ABSTRACT FROM AUTHOR]

A novel method for the selective synthesis of ( Z)-1,5-dien-2-yl esters has been developed though Pt(II)-catalyzed tandem 1,2-acyl and 1,2-hydride migration, along with an allyl migration reaction of propargylic carboxylates with electronically unbiased internal alkynes. The unusual selectivity of 1,2-acyloxy migration was realized. [ABSTRACT FROM AUTHOR]

Copper-catalyzed [4 + 1] cycloaddition reaction of α,β- acetylenic ketones with α-diazo esters offers an efficient, direct route to highly substituted furans. The reaction conditions and the scope of the process are examined, and a possible mechanism is proposed. [ABSTRACT FROM AUTHOR]