Chemistry of unprotected amino acids in aqueous solution: direct bromination of aromatic amino acids with bromoisocyanuric acid sodium salt under strong acidic condition.
Brominations of unprotected aromatic amino acids such as phenylalanine, tyrosine, and glycine, with bromoisocyanuric acid mono sodium salt (BICA-Na) were conducted in 60% aq. H(2)SO(4) at 0 degrees C to give a mixture of mono-brominated products in good yield. Unexpectedly, meta-bromophenylglycine was obtained as main product accompanied by ortho- and para-substituted products, while phenylalanine gave only ortho- and para-substituted products. Bromination of 2-phenylethylamine or benzylamine showed a tendency similar to the corresponding amino acids.
Yokoyama
Yuusaku
Y
Department of Pharmaceutical Sciences, Toho University. yokoyama@phar.toho-u.ac.jp
Yamaguchi
Tomotsugu
T
Sato
Masanori
M
Kobayashi
Eri
E
Murakami
Yasuoki
Y
Okuno
Hiroaki
H
D024322:Amino Acids, Aromatic / Q000737:chemistry*; D001966:Bromine / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D014227:Triazines / Q000737:chemistry*
D024322:Amino Acids, Aromatic; D014227:Triazines; C516817:bromoisocyanuric acid; D001966:Bromine