Metal-catalyzed amination of organic sulfonates to organic amines
申请人:Yale University
公开号:US05817877A1
公开(公告)日:1998-10-06
A process of preparing an organic amine having at least one unsaturated group, such as an arylamine, involving contacting an unsaturated organic sulfonate, such as an aryl sulfonate, with a reactant amine, such as an alkyl or aryl amine, in the presence of a base and a transition metal catalyst under reaction conditions. The transition metal catalyst contains a Group 8 metal and a chelating ligand, for example a Group 15-substituted arylene or Group 15-substituted metallocene, such as 1,1'-bis(diphenylphosphino)-2,2'-binaphthyl or 1,1'-bis(diphenylphosphino)-ferrocene, respectively. The aryl sulfonate can be prepared from a phenol and sulfonating agent.
An object is to provide an external preparation for skin preferably usable to prevent or ameliorate pigmentation. The object is achieved by providing a preventing or ameliorating agent for pigmentation, consisting of a compound represented by the following general formula (1), an isomer thereof, and/or a pharmacologically acceptable salt thereof, and an external preparation for skin containing the same as a component:
[wherein R
1
represents an unsubstituted aromatic group or an aromatic group having any substituent; R
2
represents a hydrogen atom, a linear chain or branched chain alkyl group having a number of carbon atom or atoms of 1 to 4, or an acyl group having a linear or branched alkyl chain having a number of carbon atom or atoms of 1 to 4; and R
3
represents a hydrogen atom or a linear chain or branched chain alkyl group having a number of carbon atom or atoms of 1 to 4.]
A simple and efficient catalyst-free chemoselective reductive amination of primary amines and aldehydes to synthesis of tertiary and secondaryamines with borane complex was developed. Primary amines are converted into tertiary and secondaryamines in one pot reaction under mild condition with good functional group compatibility and It does not require any catalyst to participate in this reaction.
PROPHYLACTIC OR AMELIORATING AGENT FO PIGMENTATION
申请人:Pola Chemical Industries Inc.
公开号:EP2514402A1
公开(公告)日:2012-10-24
An object is to provide an external preparation for skin preferably usable to prevent or ameliorate pigmentation. The object is achieved by providing a preventing or ameliorating agent for pigmentation, consisting of a compound represented by the following general formula (1), an isomer thereof, and/or a pharmacologically acceptable salt thereof, and an external preparation for skin containing the same as a component:
[wherein R1 represents an unsubstituted aromatic group or an aromatic group having any substituent; R2 represents a hydrogen atom, a linear chain or branched chain alkyl group having a number of carbon atom or atoms of 1 to 4, or an acyl group having a linear or branched alkyl chain having a number of carbon atom or atoms of 1 to 4; and R3 represents a hydrogen atom or a linear chain or branched chain alkyl group having a number of carbon atom or atoms of 1 to 4.]