Ethyl 2,2-bis(4-methylphenylsulfonamido)acetate to aromatic α-amino acids: stable substrates for catalytic arylation reactions
摘要:
This paper reports the development of a novel methodology for the catalytic synthesis of aromatic alpha-amino acids, which involves the addition of aryl-organoboron reagents to alpha,alpha-ditosylamino esters derived from ethyl glyoxylate, using transition metal catalysts, like Rh and Pd. A library of alpha-amino esters (12 with Pd and 8 with Rh), was synthesized with moderate to excellent yields. A highest enantioselectivity of 30% ee was obtained using Hayashi's ligand. This method was applied to the synthesis of phenylglycine. (C) 2013 Elsevier Ltd. All rights reserved.
Catalytic, enantioselective alkylations of N,O- and N, N-acetals and hemiacetals
作者:Dana Ferraris、Brandon Young、Travis Dudding、William J. Drury、Thomas Lectka
DOI:10.1016/s0040-4020(99)00450-0
日期:1999.7
We report the first examples of catalytic, enantioselective alkylation of N,O-acetals to produce useful amino acid derivatives 5 in high yield (73–93%) and enantioselectivity (70–96%). We have extended the utility of our reaction to include a simple one-pot procedure from readily available starting materials. We also provide several different N-based protecting groups that greatly increase the flexibility
Ethyl 2,2-bis(4-methylphenylsulfonamido)acetate to aromatic α-amino acids: stable substrates for catalytic arylation reactions
作者:Carolina S. Marques、Anthony J. Burke
DOI:10.1016/j.tet.2013.09.053
日期:2013.11
This paper reports the development of a novel methodology for the catalytic synthesis of aromatic alpha-amino acids, which involves the addition of aryl-organoboron reagents to alpha,alpha-ditosylamino esters derived from ethyl glyoxylate, using transition metal catalysts, like Rh and Pd. A library of alpha-amino esters (12 with Pd and 8 with Rh), was synthesized with moderate to excellent yields. A highest enantioselectivity of 30% ee was obtained using Hayashi's ligand. This method was applied to the synthesis of phenylglycine. (C) 2013 Elsevier Ltd. All rights reserved.