Benzyl succinimido carbonate → (R)-Benzyl methyl(1,2,3,4-tetrahydroquinolin-3-yl)carbamate

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Reaction Steps

A mixture of (R)-1,2,3,4-tetrahydro-N-methyl-3-quinolinamine of crude material prepared above (V, EXAMPLE 4, 15.0 g), approximately 84.4 mmol) in toluene (50 ml) is stirred at −40° while N-(benzyloxycarbonyloxy)succinimide (24.2 g, 97.1 mmol) in toluene (150 ml) is added over one hr. After 30 min at −40°, GLC analysis indicated that all of (V) had been consumed. The mixture is quenched by the addition of sodium bicarbonate (10% aqueous solution, 300 ml) and warmed to 0°, followed by the addition of methanol (100 ml). This is stirred overnight and then extracted with ethyl acetate. Drying over magnesium sulfate and solvent removal gives a liquid which is purified by flash chromatography (230-400 mesh silica gel; hexane/ethyl acetate, 4/1) which crystallized from ethyl acetate/hexane to give the title compound, mp=80°; NMR (CDCl3) 2.88, 2.80-3.04, 3.30, 3.83, 4.57, 5.16, 6.51, 6.64, 6.96-7.02 and 7.35 δ; [a]25D=−50.1° (CH3OH, c=0.816); IR (mineral oil) 1680 and 1606 cm−1.

Provenance & Evidence