手性相转移催化剂的合成和不对称诱导效应——以L-酪氨酸为原料合成的手性单季铵盐和双季铵盐

Synthesis and asymmetric induction effect of chiral phase transfer catalyst——chiral quarternary and bisquarternary ammonioum salts synthesized with L-(-)-tyrosine

以L-(-)-酪氨酸为原料,经氨基保护、醚化、酯化等步骤制得L-(-)-对甲氧基苯丙氨酸(1),化合物1经NaBH4还原得到L-(-)-对甲氧基苯丙氨醇(2)。以化合物1和2为原料,经过季铵化合成了4种手性单季铵盐和2种手性双季铵盐。6种手性季铵盐作为相转移催化剂,在α-羟基苯乙酸的合成中显示出良好的催化作用和一定的不对称诱导效应。

The L-（ - ）-4-Methyloxophenylalanine （ 1 ） was synthesized by using L-（ - ）-tyrosine as the raw material through amino protection, etherification and esterification. The L- （ - ）-3- paramthyloxylphenyl-2-aminopropanol（2）was obtained by reduc- tion of 1 with NaBH4. Using 1 and 2 as raw material, four chiral quartemary ammonioum salts and two ehiral diquartemary ammonioum salts were synthesized by quaterisation. As the phase transfer catalyst,all these chiral quarternary ammonioum salts showed an excellent phase transfer catalysis and displayed a certain asymmetrical induction effect in the synthesis of a-hydroxylphenylpropanoic acid.