Studien zum Reaktionsmechanismus der Hydantoin-Synthese nachBiltz, 1. Mitt.: Nachweis der Zwischenstufen der Hydantoin-Synthese nachBiltz
作者:Gerhard Schwenker、Hong Guo、Sonja Bernhart
DOI:10.1002/ardp.19923251207
日期:——
Der von Butler und Leitch vorgeschlagene Reaktionsmechanismus für die bei der Hydantoinsynthese von Biltz ablaufende Skelett‐Umlagerung konnte gesichert werden. Die bereits von Biltz postulierte Zwischenstufe 3a wurde aus dem Reaktionsansatz isoliert und die Zwischenstufen 3b‐3g und 4b‐4g auf unabhängigem Wege synthetisiert und in den Reaktionsansätzen der jeweiligen Benzile 1b‐1d mit Phenylharnstoff
Mechanistic Insights on the Mechanosynthesis of Phenytoin, a WHO Essential Medicine**
作者:Francesco Puccetti、Stipe Lukin、Krunoslav Užarević、Evelina Colacino、Ivan Halasz、Carsten Bolm、José G. Hernández
DOI:10.1002/chem.202104409
日期:2022.3
In situ monitoring by Raman spectroscopy of the mechanosynthesis of phenytoin, a World Health Organization EssentialMedicine, is reported. This study enabled the observation, isolation and characterization of key molecular-migration intermediates involved in the transformation of benzil (1), urea (2), and KOH into phenytoin (3). The depth of this investigation answers scientifically interesting questions
A convenient preparation of symmetrical and unsymmetrical 1,2-diketones: application to fluorinated phenytoin synthesis
作者:Philip C. Bulman Page、Andrew E. Graham、B.Kevin Park
DOI:10.1016/s0040-4020(01)88265-x
日期:1992.1
1,2-Diketones are efficiently produced in two steps by reaction of aldehydes with anions derived from 2-substituted dithianes followed by treatment of the resulting alcohols with NBS in aqueous acetone; phenytolin derivatives were prepared from these diketones by a standard method involving treatment with urea and potassium hydroxide under reflux.
FORMALDEHYDE FREE BINDER COMPOSITIONS WITH UREA-ALDEHYDE REACTION PRODUCTS
申请人:JOHNS MANVILLE
公开号:US20160289258A1
公开(公告)日:2016-10-06
Fiber-containing composites are described that contain woven or non-woven fibers, and a cured binder formed from a binder composition that includes (1) a reducing sugar and (2) a crosslinking agent that includes a reaction product of a urea compound and a polycarbonyl compound. Exemplary reaction products for the crosslinking agent may include the reaction product of urea and an α,β-bicarbonyl compound or an α,γ-bicarbonyl compound. Exemplary fiber-containing composites may include fiberglass insulation.
Formaldehyde free binder compositions with urea-aldehyde reaction products
申请人:JOHNS MANVILLE
公开号:US10570271B2
公开(公告)日:2020-02-25
Fiber-containing composites are described that contain woven or non-woven fibers, and a cured binder formed from a binder composition that includes (1) a reducing sugar and (2) a crosslinking agent that includes a reaction product of a urea compound and a polycarbonyl compound. Exemplary reaction products for the crosslinking agent may include the reaction product of urea and an α,β-bicarbonyl compound or an α,γ-bicarbonyl compound. Exemplary fiber-containing composites may include fiberglass insulation.