Triethylamine → 2-(Trimethylsilyl)ethyl 4-((2-(dimethoxymethyl)-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)methyl)-3-oxopiperazine-1-carboxylate

Participants

Reaction Steps

A mixture of 2-(dimethoxymethyl)-5,6,7,8-tetrahydro-1,8-naphthyridine-3-carbaldehyde (intermediate 41, 2.50 g, 10.58 mmol), ethyl 2-((2-aminoethyl)((2-(trimethylsilyl)ethoxy)carbonyl)amino)acetate para-toluene sulphonate (intermediate 124, 8.37 g, 18.09 mmol) and triethylamine (3.23 ml, 23.28 mmol) in 1,2-dichloroethane (10 ml) at room temperature was stirred for 12 h and sodium triacetoxyborohydride (4.72 g, 21.16 mmol) added. The reaction mixture was stirred for 18 h at room temperature, partitioned between saturated aqueous NaHCO3 solution and EtOAc, the EtOAc phase washed with brine, dried over MgSO4 and evaporated. The residue was applied to a RediSep® silica column and purified by normal phase chromatography, eluting with a gradient from heptane to EtOAc. Product containing fractions were combined and evaporated to give the title compound as a yellow oil. (UPLC-MS 6) tR 0.42; ESI-MS 322.2 [M+H]+.

Provenance & Evidence