947-65-9Relevant articles and documents
Naphthyl ester synthesis using 1,3-dicyclohexylcarbodiimide
Zengin, Gulay,Huffman, John W.
, p. 1932 - 1934 (2004)
Dicyclohexylcarbodiimide (DCC) has been used in the past as a condensing agent in ester synthesis. Yields of ester using this route have been reported as unsatisfactory due to the formation of the by-product, an N-acylurea compound. A catalytic amount of p-toluenesulfonic acid in addition to DCC was used for the synthesis of naphthyl esters. Several other attempts to achieve esterification were also tried but were found to be unsuccessful. One method involved the in situ generation of the carboxylate anion in DMF by the use of a base followed by subsequent alkylation with an alkyl halide. Another method attempted for esterification was acylation of a carboxylic acid. The preferred method for the synthesis of a naphthyl ester was that using DCC as the condensing agent with catalytic amounts of a strong acid.
Size-Driven Inversion of Selectivity in Esterification Reactions: Secondary Beat Primary Alcohols
Mayr, Stefanie,Marin-Luna, Marta,Zipse, Hendrik
, p. 3456 - 3489 (2021/03/01)
Relative rates for the Lewis base-mediated acylation of secondary and primary alcohols carrying large aromatic side chains with anhydrides differing in size and electronic structure have been measured. While primary alcohols react faster than secondary ones in transformations with monosubstituted benzoic anhydride derivatives, relative reactivities are inverted in reactions with sterically biased 1-naphthyl anhydrides. Further analysis of reaction rates shows that increasing substrate size leads to an actual acceleration of the acylation process, the effect being larger for secondary as compared to primary alcohols. Computational results indicate that acylation rates are guided by noncovalent interactions (NCIs) between the catalyst ring system and the DED substituents in the alcohol and anhydride reactants. Thereby stronger NCIs are formed for secondary alcohols than for primary alcohols.
Visible Light-Promoted Photocatalytic C-5 Carboxylation of 8-Aminoquinoline Amides and Sulfonamides via a Single Electron Transfer Pathway
Sen, Chiranjit,Sahoo, Tapan,Singh, Harshvardhan,Suresh, Eringathodi,Ghosh, Subhash Chandra
, p. 9869 - 9896 (2019/08/20)
An efficient photocatalytic method was developed for the remote C5-H bond carboxylation of 8-aminoquinoline amide and sulfonamide derivatives. This methodology uses in situ generated ?CBr3 radical as a carboxylation agent with alcohol and is further extended to a variety of arenes and heteroarenes to synthesize the desired carboxylated product in moderate-to-good yields. The reaction proceeding through a single electron transfer pathway was established by a control experiment, and a butylated hydroxytoluene-trapped aryl radical cation intermediate in high-resolution mass spectrometry was identified.
Design and Synthesis of a Series of l-trans-4-Substituted Prolines as Selective Antagonists for the Ionotropic Glutamate Receptors Including Functional and X-ray Crystallographic Studies of New Subtype Selective Kainic Acid Receptor Subtype 1 (GluK1) Antagonist (2S,4R)-4-(2-Carboxyphenoxy)pyrrolidine-2-carboxylic Acid
Krogsgaard-Larsen, Niels,Delgar, Claudia G.,Koch, Karina,Brown, Patricia M. G. E.,M?ller, Charlotte,Han, Liwei,Huynh, Tri H. V.,Hansen, Stinne W.,Nielsen, Birgitte,Bowie, Derek,Pickering, Darryl S.,Kastrup, Jette Sandholm,Frydenvang, Karla,Bunch, Lennart
, p. 441 - 457 (2017/04/26)
Ionotropic glutamate receptor antagonists are valuable tool compounds for studies of neurological pathways in the central nervous system. On the basis of rational ligand design, a new class of selective antagonists, represented by (2S,4R)-4-(2-carboxyphenoxy)pyrrolidine-2-carboxylic acid (1b), for cloned homomeric kainic acid receptors subtype 1 (GluK1) was attained (Ki = 4 μM). In a functional assay, 1b displayed full antagonist activity with IC50 = 6 ± 2 μM. A crystal structure was obtained of 1b when bound in the ligand binding domain of GluK1. A domain opening of 13-14° was seen compared to the structure with glutamate, consistent with 1b being an antagonist. A structure-activity relationship study showed that the chemical nature of the tethering atom (C, O, or S) linking the pyrrolidine ring and the phenyl ring plays a key role in the receptor selectivity profile and that substituents on the phenyl ring are well accommodated by the GluK1 receptor.