Synthesis and some spectral characteristics of bicyclic phosphate, GABA antagonists.
作者:Yoshihisa OZOE、Morifusa ETO
DOI:10.1271/bbb1961.46.411
日期:——
Bicyclic phosphates (BPs), GABA antagonists, were prepared by reaction of the corresponding triols with phosphoryl chloride. The triols were obtained by one of the following methods: (a) the Tollens condensation of an aldehyde possessing α-hydrogen atoms with formaldehyde; (b) the basecatalyzed hydroxymethylation of alkylmalonates or α-alkylacetoacetates with paraformaldehyde, followed by reduction; (c) the reduction of diethyl pivaloylmalonate; or (d) the halogenation of pentaerythritol. Some BPs were also derived by modification of the functional groups of BP homologs. The 1H-NMR spectra of 4-substituted BPs showed a characteristic doublet peak due to the endocyclic methylene protons, the shift position of which was affected by the electronic nature of the bridgehead substituent. The mass spectra of the PBs were characterized by peaks due to the loss of CH2O from the ring.
Manganese-catalyzed intermolecular C-H/C-H coupling of carbonyls and heteroarenes has been developed. The presence of NaIO4 as an oxidant is crucial for the catalytic reaction. These new, inexpensive reaction conditions allow the gram-scale synthesis of alpha-heteroaryl carboxylic acids.
Preparation of alpha-pivaloyl-substituted acetic acid esters
申请人:Shell Oil Company
公开号:US04656309A1
公开(公告)日:1987-04-07
An alpha-pivaloyl-substituted acetic acid ester of the formula (H.sub.3 C).sub.3 CCOCH.sub.2 COOR, wherein R is an optionally-substituted alkyl, aryl, alkaryl, or aralkyl group, is prepared by (a) reacting an alpha-pivaloyl-substituted malonic acid ester with a base selected from the class consisting of alkali metal alkoxides and compounds of the formula MXY, wherein M is an alkaline earth metal, X is an alkoxy group, and Y is either an alkoxy group or a halogen atom, and (b) acidifying the resulting reaction mixture.
EFFICIENT SYNTHESIS OF 4-ETHOXYCARBONYL PYRAZOLIN-5-ONE DERIVATIVES
作者:Jae C. Jung、E. Blake Watkins、Mitchell A. Avery
DOI:10.1081/scc-120015395
日期:2002.1.1
Concise and efficient methods for the preparation of 3-substituted 4-ethoxycarbonylpyrazolin-5-ones are described. The synthetic strategies involve carbon-acylation in the presence of base, followed by ring cyclization With hydrazine or hydrazine monohydrochloride.
Hormi, Osmo E. O., Synthetic Communications, 1986, vol. 16, # 9, p. 997 - 1002