摘要:
Die vorliegende Erfindung betrifft ein leicht zugängliches und vielseitig verwendbares Verfahren zur Herstellung von Carbamaten, Harnstoffen und aromatischen Aminen über eine basenkatalysierte Lossen-Umlagerung. Insbesondere Carbamate und Amine sind wichtige Grundstoffe der chemischen Industrie. Das Verfahren wird in Abwesenheit aggressiver Reagenzien durchgeführt und bedarf der Anwesenheit eines organischen Carbonats sowie der katalytischen Menge eines tertiären Amins als Base. Die Reaktionsbedingungen des erfindungsgemäßen Syntheseverfahrens sind mild wodurch ggf. funktionelle Gruppen oder Doppelbindungen nicht modifiziert werden.
摘要:
Verfahren zur Herstellung von mindestens drei isocyanatgruppen aufweisenden Allophanatpolyisocyanaten, bei welchem überschüssige Mengen an organischen Allophanatgruppen-freien Polyisocyanaten mit ausgewählten, Hydroxylgruppen und Urethangruppen aufweisenden Verbindungen zur Umsetzung gebracht werden. Die Produkte dienen als Aufbaukomponente bei der Herstellung von Polyurethankunststoffen.
摘要:
The present invention provides methods of forming carbamates, ureas, and isocyanates. In certain embodiments these methods include the step of reacting an amine with an ester-substituted diaryl carbonate to form an activated carbamate which can be further derivitized to form non-activated carbamate or a urea. The urea or carbamate can be subjected to a pyrolysis reaction to form isocyanate.
摘要:
Disclosed is an improved multi-step process for preparing a compound of Formula I and intermediates used therein: (I) wherein R1 to R3 are as defined herein. The compounds of formula I inhibit the binding of human intercellular adhesion molecules to the Leukointegrins. As a result, these compounds are useful in the treatment of inflammatory and immune cell-mediated diseases.
摘要:
A method of producing a pantothenic acid derivative of formula (I):
wherein each of R¹ and R² is different, and is a branched aliphatic hydrocarbon group having 3 to 5 carbon atoms, or a phenyl group; or a straight chain aliphatic hydrocarbon group having 5 to 10 carbon atoms, is provided, including methods of producing the starting materials for producing the same and novel amine derivative that can be used for the production of the pantothenic acid derivative.
摘要:
A method for producing an alkylamine derivative having a urea bond represented by formula (I), or a salt thereof, comprises the following steps (a) and (b), step (a):
and step (b): deprotecting as necessary the reaction product obtained in step (a). The production method suitable for industriallization of the alkylamine derivative having a urea bond represented by formula (I), which is a compound highly useful as an agent having CaSR agonist effects is provided.
摘要:
The present invention relates to a safe and efficient process for the preparation of carmustine (1) and to useful intermediate compounds of such process and their preparation. Such process employs safe and readily available starting materials under mild reaction conditions and allows for recovery of the product in a good yield and a high purity. For these reasons, such new process is also suitable for plant scale production. Starting materials comprise 2-chloroethylamine hydrochloride (5) and 1,1'-carbonyldiimidazole (4) to afford 1,3-bis(2-chloroethyl)-1-urea (2), which then undergoes nitrosation to give the final product.