摘要:
A process for preparing carbamates having the general formula I: wherein R¹ represents a hydrogen atom or an alkyl group, R² represents an optionally substituted aryl group and R³ represents an alkyl, haloalkyl, alkenyl, haloalkenyl, alkynyl, haloalkynyl group or an optionally substituted aryl or heteroaryl group, comprises reacting an amine having the general formula II: wherein R¹ and R² are as hereinbefore defined, or a symmetrical urea having the general formula III: wherein R¹ and R² are as hereinbefore defined, carbon monoxide and oxygen in the presence of a catalyst comprising:
a) palladium; b) an organo-nitrogen or organo-phosphorous ligand having a lone pair of electrons; and c) a metal salt comprising a cation of a metal selected from the group consisting of copper, iron, vanadium, chromium, zinc, tin, uranium and cerium, and an anion of an acid having a pK of less than 2, except of a hydrohalogenic acid.
摘要:
A process for the preparation of phenyl ureas, which comprises reacting a nitrobenzene with an amine and carbon monoxide at an elevated temperature in the presence of a palladium catalyst, the amine being supplied continuously or stepwise during the period of the reaction.
摘要:
A process for preparing aromatic ureas having the general formula I: wherein each of R¹ and R³ independently represents a hydrogen atom, an alkyl or cycloalkyl group, R² represents an optionally substituted aryl or heteroaryl group, and R⁴ represents an alkyl, alkenyl, alkynyl or alkoxy group, or an optionally substituted cycloalkyl, aryl or heteroaryl group, which process comprises reacting an aromatic amine having the general formula II: wherein R¹ and R² are as hereinbefore defined, or a symmetrical aromatic urea having the general formula III: wherein R¹ and R² are as hereinbefore defined, with an amine having the general formula IV: wherein R³ and R⁴ are as hereinbefore defined, and carbon monoxide in the presence of a catalyst comprising:
a) palladium; b) an organo-nitrogen or organo-phosphorous ligand having a lone pair of electrons; and c) a metal salt comprising a cation of a metal selected from the group consisting of copper, iron, vanadium chromium, zinc, tin, uranium and cerium, and an anion of an acid having a pK of less than 2, except of a hydrohalogenic acid.
摘要:
A process for the preparation of phenyl ureas, which comprises reacting a nitrobenzene with an amine and carbon monoxide at an elevated temperature in the presence of a palladium catalyst, the amine being supplied continuously or stepwise during the period of the reaction.
摘要:
A process for the preparation of linear olefins comprises reacting ethene with at least one further alpha olefin under oligomerizing conditions in the presence of a catalyst system comprising a combination of a first component which is a bis(cyclopentadienyl) Group IVA metal compound containing a substituent capable of reacting with a cation and a second component which is a compound having a bulky anion containing a plurality of boron atoms and which is substantially non-coordinating under the reaction conditions and a cation, and recovering an oligomeric product comprising linear olefins.
摘要:
A process for the preparation of a compound of general formula in which R¹ represents a hydrogen atom or a methyl group, one of R² and R³ represents a hydrogen atom and the other of R² and R³ is the same as R¹, which comprises reacting a compound of general formula R¹-CH=C=CH₂ (II) with a salt of formic acid in the presence of a catalyst system comprising a palladium salt and a phosphorus compound of general formula P(OX) n (X) 3-n (III) in which n is 0,1,2 or 3 and each X independently represents an alkyl, alkenyl, aryl, aralkyl, alkaryl or cycloalkyl group, and recovering the desired compound of formula (I).