HCID 13151114, compound → HCID 13151115, compound

Participants

Reaction Steps

A solution of 5-benzyloxy-4-hydroxy-2-pentynal diethyl acetal (43.2 g) in abs. ethanol (250 ml) is hydrogenated in the presence of 82.7% platinum oxide (1.4 g), sodium nitrite (14 mg) and 1 drop of water for 90 minutes in a Parr hydrogenation apparatus. The reaction is repeated exactly as above with another (43.2 g) portion of 5-benzyloxy-4-hydroxy-2-pentynal diethyl acetal; the two mixtures are combined and the catalyst is removed by filtration through a bed of celite and washed with ethanol. The combined filtrate is evaporated in vacuo to give a residue (89.4 g, 100%). A 200 mg portion of the residue is purified on Quantagram PQ1F plates (developed in 40% CHCl3 /hexane three successive times). The principal band is eluted with ethyl acetate and the solvent is evaporated in vacuo to give 5-benzyloxy-4-hydroxypentanal diethyl acetate (152 mg); ir (neat) 2.88 μ (OH); nmr (CDCl3,δ): 1.17 (t, 6 H, OCH2CH3), 1.62 (m, 4H, CHCH2CH2CH), 2.7 (b, 1H, >CH-OH), 3.53 (m, 7H, OCH2CH3 and OCH2CH and ##STR6## 4.47 (m, 1H, >CHOH), 4.5 (s, 2H φCH2O), 7.28 (s, 5H, φCH2O).

Provenance & Evidence