Alkylation

About: Alkylation is a research topic. Over the lifetime, 29915 publications have been published within this topic receiving 464944 citations. The topic is also known as: alkylation reaction.

Process for alkylating aromatic compounds

Abstract: Aromatics are alkylated with C 2+ alkyl groups using as alkylating agents mixtures of hydrogen/hydrogen precursors and carbon oxide, preferably syngas, over catalysts comprising a zeolite of Constraint Index not above 12 and a metal component selected from Fe, Co, Ru, Mn, Rh and Os. The alkylation products can be dealkylated to produce olefins and aromatics.

Enantioselective intramolecular hydroarylation of alkenes via directed C-H bond activation.

Abstract: Highly enantioselective catalytic intramolecular ortho-alkylation of aromatic imines containing alkenyl groups tethered at the meta position relative to the imine directing group has been achieved using [RhCl(coe)2]2 and chiral phosphoramidite ligands. Cyclization of substrates containing 1,1- and 1,2-disubstituted as well as trisubstituted alkenes were achieved with enantioselectivities >90% ee for each substrate class. Cyclization of substrates with Z-alkene isomers proceeded much more efficiently than substrates with E-alkene isomers. This further enabled the highly stereoselective intramolecular alkylation of certain substrates containing Z/E-alkene mixtures via a Rh-catalyzed alkene isomerization with preferential cyclization of the Z-isomer.

Crystal-structure-based design and synthesis of benz[cd]indole-containing inhibitors of thymidylate synthase.

Abstract: The X-ray crystal-structure-based design, synthesis, and biological activity of a novel family of benz[cd]indole-containing inhibitors of thymidylate synthase (TS) are described The structure-activity of the lead compound was studied by conceptually dividing the molecule into four regions and independently optimizing the substituents for each region Combination of favored substituents for each region led to inhibitors with Ki's against the human enzyme in the range of 10-20 nM Thymidine shift experiments suggested that the cytotoxic properties of the best enzyme inhibitors were due to TS targeting in cells The inhibitors were synthesized from substituted 6-aminobenz[cd]indol-2(1H)-ones by alkylation with both a simple alkyl group and a substituted benzylic portion The 2,6-diaminobenz[cd]indoles were prepared from the corresponding lactams by conversion to the thiolactam, alkylation to the methylated thiolactam, and then displacement with a substituted or unsubstituted amine

Enantio- and Diastereoselective Synthesis of 1,2-Hydroxyboronates through Cu-Catalyzed Additions of Alkylboronates to Aldehydes

Abstract: The first catalytic enantio- and diastereoselective synthesis of 1,2-hydroxyboronates is reported. Reactions are promoted by a readily available chiral monodentate phosphoramidite–copper complex in the presence of an alkyl 1,1-diboron reagent. Products contain two contiguous stereogenic centers and are obtained in up to 91% yield, >98:2 d.r., and 98:2 e.r. The reaction is tolerant of aryl and vinyl aldehydes, and the 1,2-hydroxyboronate products can be transformed into versatile derivatives. Mechanistic experiments indicate control of absolute stereochemistry of the α-boryl component.

Fluoride Salts on Alumina as Reagents for Alkylation of Phenols and Alcohols

Abstract: The effectiveness of alkali metal fluorides impregnated on alumina as a reagent for promoting alkylation was optimized with respect to the metal cation, the amount of impregnation, and the reaction solvent. Potassium or caesium fluoride on alumina in acetonitrile or 1,2-dimethoxyethane was concluded to be the best reaction system for general use. O-Alkylation of substituted phenols, primary and secondary alcohols, and a glycol was carried out mostly in good yields under mild conditions with simple experimental procedures.