Pd(OAc)2-Catalyzed Carbonylation of Amines

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• 作者：Kazuhiko Orito ; Mamoru Miyazawa ; Takatoshi Nakamura ; Akiyoshi Horibata ; Harumi Ushito ; Hideo Nagasaki ; Motoki Yuguchi ; Satoshi Yamashita ; Tetsuro Yamazaki ; Masao Tokuda
• 刊名：Journal of Organic Chemistry
• 出版年：2006
• 出版时间：August 4, 2006
• 年：2006
• 卷：71
• 期：16
• 页码：5951 - 5958
• 全文大小：258K
• 年卷期：v.71,no.16(August 4, 2006)
• ISSN：1520-6904

文摘

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A phosphine-free catalytic system [Pd(OAc)₂-Cu(OAc)₂-air] induced a substrate-specific carbonylationof amines in boiling toluene under CO gas (1 atm). Symmetrical N,N'-dialkylureas were obtained by thecarbonylation of primary amines. N,N,N'-Trialkylureas were selectively formed by addition of a secondaryamine to the above reaction vessel. Secondary amines did not give tetraalkylureas. However, dialkylamineswith a phenyl group on their alkyl chains, such as N-monoalkylated benzylic amine or phenethylaminederivatives, underwent a direct aromatic carbonylation to afford five- or six-membered benzolactams. Inthe carbonylation, the chelation effect or steric repulsion between Pd(II) and the meta-substituent in theortho-palladation and the ring sizes of cyclopalladation products that were formed prior to carbonylationwere found to generate good site selectivity and increase the reaction rate. In contrast, carbonylation ofs/gifchars/omega.gif" BORDER=0 >-arylalkylamines with a hydroxyl group gave neither ureas nor benzolactams but instead produced 1,3-oxazolidinones smoothly. Hydrochlorides of amines also underwent carbonylation to afford thecorresponding amides under the conditions used. This procedure made it possible to prepare ureas ofamino acid esters and N-alkylcarbamates in practical yields.