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

dissolved in 1,Qdioxane (200 mL), slowly added to the stirring mixture which was then
allowed to warm to rwm temperature. After 24 hours, the volume was reduced to
approximately 200 mL under vacuum, then de-ionized water (10 mL) added and the
final pH of the mixture adjusted to 3 with 1M Ha. This was then extracted with CH2C12
(3 x 150 mL), the organic extracts were then pooled and extracted with saturated
NaHC03 (3 x 100 mi,). The aqueous extracts were pooled, chilled to O°C, acidified to
pH 3 with 1M HCI then extracted with CH2C12 (4 x 100 mL). The organic extracts were
pooled, extracted with brine (50 mL) then dried over MgSQ and the solvent removed
under reduced pressure to yield a colourless oil which solidified upon standing and was
used without further purification.
TU3 (111, CHCl,:EtOAc, 1% ACOH) Rr= 0.18; 'H NMR (CDC13, 300 MHz) 6 10.72 (br
s, lH, CO& 7.31-7.26 (m, 5H, ArH), 5.61 (d, lH, J=7.5Hz, Nn), 5.08 (s, 2H,
CbzCHzO), 4.60-4.42 (m. 1 H, a-CH), 3.63 (s, 3H, CO2CH3). 2.50-2.33 (m, 2H, y-CH2),
2.30-2.16 (m, 1H, p-CHH), 2.09-1.9 1 (m, LH, p-CHH); "C NMR (CDC13, 75 MHz) 6
176.1 CO), 173.6 c=O), 156.3 (CONH), 136.1 (Cbz===), 128.6, 128.3, 128.2
(Cbz