Results 171 to 180 of about 9,205 (206)

Conductivities of 1:1 electrolytes in mixed aprotic solvents—II. dimethoxyethane mixtures with propylene carbonate and 4-butyrolactone

Electrochimica Acta, 1985
Abstract The conductivities of five 1:1 electrolytes have been measured in mixtures of dimethoxyethane with propylene carbonate and 4-butyrolactone. As in previous studies involving mixed ethereal solvents, a maximum in the molar conductances is found for a specific solvent mixture. From consideration of single ion mobilities, Stokes' radii, and the
M. Salomon, E.J. Plichta
openaire   +1 more source

High reactivity of alkyl sulfides towards epoxides under conditions of collagen fixation—a convenient approach to 2-amino-4-butyrolactones

Biomaterials, 2001
Epoxy crosslinking agents have been investigated for use in the fabrication of bioprosthetic devices, such as heterograft heart valve prostheses. It has been generally assumed that epoxy crosslinking takes place via amino-epoxy reactions. The present study investigated the hypothesis that the reactions of methionine residues with epoxides also can ...
I S, Alferiev, J T, Hinson, M, Ogle, E, Breuer, R J, Levy   +4 more
openaire   +2 more sources

Sodium Dithionite Initiated Addition‐lactonization of 2‐Acyl‐ amino‐4‐pentenoic Acids with Fluoroalkyl Iodides to Synthesize 4‐Fluoroalkyl‐2‐acylamino‐4‐butyrolactones

Chinese Journal of Chemistry, 2010
Abstract4‐Fluoroalkyl‐2‐acylamino‐4‐butyrolactones were afforded in moderate yields by the sodium dithionite initiated one‐pot addition‐lactonization reaction of polyfluoroalkyl iodides with 2‐acylamino‐4‐pentenoic acids.
Xueyan Yang, Xianjin Yang, Shengjie Zhu, Lingling Ye, Yang Chen, Guanlong Chen, Fanhong Wu   +6 more
openaire   +1 more source

Absolute configuration of aromatic oxygenated isoprenoid derivatives: formation of 3-hydroxy-4,4-dimethyl-4-butyrolactone by ozonolysis and a study of its stereochemistry

Journal of the Chemical Society, Perkin Transactions 1, 1973
Ozonolysis of the hydroxyisopropylfuroquinoline alkaloid, platydesminium metho-salt, afforded (+)-3-hydroxy-4,4-dimethyl-4-butyrolactone. The structure of the lactone was established by asymmetric synthesis of its formate ester and its absolute configuration by correlation with (–)-4-methylpentane-1,3-diol.
J. F. Collins, M. F. Grundon
openaire   +1 more source

ChemInform Abstract: Sodium Dithionite Initiated Addition—Lactonization of 2‐Acylamino‐4‐pentenoic Acids with Fluoroalkyl Iodides to Synthesize 4‐Fluoroalkyl‐2‐acylamino‐4‐butyrolactones.

ChemInform, 2011
AbstractOptimum reaction conditions are studied.
Xueyan Yang, Xianjin Yang, Shengjie Zhu, Lingling Ye, Yang Chen, Guanlong Chen, Fanhong Wu   +6 more
openaire   +1 more source

The formation of cation-ligand complexes of tributylammonium cation with diethyl carbonate, ethylene carbonate, propylene carbonate, 4-butyrolactone, ethyl acetate, and cyclopentanone ino-dichlorobenzene at 25�C

Journal of Solution Chemistry, 1979
The effects of adding millimolar quantities of a series of compounds containing the carbonyl function on the conductances of solutions (0.2 mM) of tri-n-butylammonium picrate ino-dichlorobenzene solvent at 25°C have been measured. Values of the complex formation constants K 1 + for 1:1 cation-ligand ...
Mary Anne Jones, W. R. Gilkerson
openaire   +1 more source

Asymmetric Hydrogenation of 2,4-Dioxo Esters: Selective Synthesis of 2-Hydroxy-4-oxo Esters and Direct Access to Chiral 2-Hydroxy-4-butyrolactones

European Journal of Organic Chemistry, 1999
2,4-Dioxoesters 1a–c are selectively converted into optically active 2-hydroxy-4-oxoesters 2a–c by hydrogenation with chiral rhodium-aminophosphane-phosphinite catalysts (82–88% ee) or ruthenium-bisphosphane catalysts (52–67% ee). Direct one-pot hydrogenation of 2,4-dioxoesters 1a–c to 2-hydroxy-4-butyrolactones 4a–c proceeds in high yields; catalytic ...
Véronique Blandin, Jean-François Carpentier, André Mortreux   +2 more
openaire   +1 more source

Palladium-Catalyzed [3 + 2] Cycloaddition of 4-Vinyl-4-Butyrolactones with Alkenes: Synthesis of Spirocyclopentane Compounds

The Journal of Organic Chemistry
A palladium-catalyzed [3 + 2] cycloaddition of 4-vinyl-4-butyrolactones (VBLs) with alkenes has been developed to afford various spirocyclopentane products in high yields with excellent diastereoselectivities. The scale-up reaction and further derivations of the product worked well, demonstrating the potential application of the current reaction in ...
Honghao Sun, Aoran Song, Shuang Gu, Yi Tang, Sen Yang, Wenhui Li, Hongchao Guo   +6 more
openaire   +2 more sources

ChemInform Abstract: ABSOLUTE CONFIGURATION OF AROMATIC OXYGENATED ISOPRENOID DERIVATIVES, FORMATION OF 3‐HYDROXY‐4,4‐DIMETHYL‐4‐BUTYROLACTONE BY OZONOLYSIS AND A STUDY OF ITS STEREOCHEMISTRY

Chemischer Informationsdienst, 1973
AbstractOzonolyse des Platydesminiummetho‐Salzes (I) liefert das Butyrolacton (IIa), dessen Struktur durch asymm. Synthese des Esters (IIb) aus dem Ester (III) über das Epoxid (IV) bestätigt wird.
J. F. COLLINS, M. F. GRUNDON
openaire   +1 more source

Palladium-Catalyzed [5 + 4] Cycloaddition of 4-Vinyl-4-Butyrolactones with N-Tosyl Azadienes: Construction of Nine-Membered Ring

The Journal of Organic Chemistry
In this paper, we reported the palladium-catalyzed formal [5 + 4] cycloaddition reactions between 4-vinyl-4-butyrolactones (VBLs) and azadienes. Under mild reaction conditions, a wide range of benzofuran-fused 9-membered heterocyclic compounds had been provided in moderate to excellent yields with exclusive regioselectivities and excellent ...
Lan Wang, Sen Yang, Yi Tang, Kuan Li, Mengxi Lu, Hongchao Guo   +5 more
openaire   +2 more sources