(S,S,S)-2-aza-bicyclo-[3.3.0]- octane-3-carboxylic acid benzyl ester, Ramipril intermediate

93779-31-8 cas

Cyclopenta[b]pyrrole-2-carboxylicacid, octahydro-, phenylmethyl ester, (2S,3aS,6aS)-

Formula:	C15H20ClNO2
Molecular Weight:	281.78

cas 93779-29-4

(S,S,S)-2-aza-bicyclo-[3.3.0]- octane-3-carboxylic acid benzyl ester

(S,S,S)-2-aza-bicyclo-[3.3.0]- octane-3-carboxylic acid benzyl ester, white solid. Yield 33.7 g (95%); mp 178–180 8C (lit.[6c] mp 180 8C); [a]D 20 ¼ 240.0 (c ¼ 1, H2O) [lit.[6c] [a]D 30 ¼ 238.4 (c ¼ 1, H2O)];

 1H NMR (400 MHz, CDCl3) d 1.36–1.42 (m, 1H), 1.58–1.75 (m, 2H), 1.82–2.01 (m, 3H), 2.32–2.37 (m, 1H), 2.58 (dt, J ¼ 13.2, 8.4 Hz, 1H), 2.83–2.88 (m, 1H), 4.31 (td, J ¼ 8.0, 3.6 Hz, 1H), 4.43 (t, J ¼ 8.4 Hz, 1H), 5.20 (AB q,J ¼ 12.0 Hz, 2H), 7.33–7.37 (m, 5H); 13C NMR (50 MHz, DMSO) d 24.07, 29.60, 31.02, 33.45, 41.37, 60.11, 63.81, 66.99, 128.11, 128.28, 128.43, 135.14, 167.32; FT IR (KBr disc) 1758 cm21; MS: m/e 246 (Mþ).

(c) Teetz, V.;
Geiger, R.; Gaul, H. Synthesis of unnatural amino acids: (S,S,S)-2-azabicyclo-
[3.3.0]-octane-3-carboxylic acid. Tetrahedron Lett. 1984, 25, 4479.