Solution and Solid Phase Synthesis of Unusual a-Amino Acids From

In 1984, a modified Strecker synthesis using TMSCN was used to prepare a
variety of racemic P,y-unsaturated amino acids in 15-688 overall yield although
vinylglycine itself was obtained in a low 7% yield (Scheme 3.6). It was noted that cation
exchange column elution of vinylglycine with 1M bH&H gave a later eluting product
identified as 2.4-diaminobutyric acid?
Scheme 3.6
A four step process that makes use of a [3,3] sigmatropic rearrangement of 3.21
gives vinylglycine 3.7 in 26% overall yield (Scheme 3.7) and has potential for industrial
application since inexpensive chernicals are used?
Scheme 3.7
A number of racernic f3,yunsaturated amino acids have been prepared by
oxidative rearrangement of allylic selenides 3.22 with yields of 12-878 reported in the
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