Yield:880347-43-3 100%

Reaction Conditions:

Stage #1: methanol;(S)-2-amino-3-(3-bromophenyl)propanoic acidwith thionyl chloride at 0 - 20; for 48 h;
Stage #2: with hydrogenchloride in water;

Steps:

1A Example 1A Methyl 3-bromo-L-phenylalaninate hydrochloride

Example 1A
Methyl 3-bromo-L-phenylalaninate hydrochloride
3-Bromo-L-phenylalanine (5 g, 19.46 mmol) was dissolved in 25 ml of methanol, the solution was cooled to 0° C. and thionyl chloride (9.26 g, 77.8 mmol) was added.
The reaction mixture was stirred at RT for 48 h and then concentrated to dryness.
This gave 5.7 g (100% of theory) of the title compound.
¹H NMR (400 MHz, DMSO-d₆): δ=ppm 3.11 (dd, 4.55 Hz, 2H), 3.66 (s, 3H), 4.29 (dd, 1H), 7.19-7.30 (m, 2H), 7.43-7.48 (m, 2H), 8.58 (br. s., 3H).
LC-MS (Method 4): R_t=0.65 min; MS (ESIpos): m/z=258 [M+H-HCl]⁺.

References:

US2016/244437,2016,A1 Location in patent:Paragraph 0759; 0760; 0761; 0762