Ammonia → (4R,6R)-tert-Butyl-6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate

HRID 466296

Reaction equation

[C:1]([CH2:3][C@H:4]1[O:9][C:8]([CH3:11])([CH3:10])[O:7][C@@H:6]([CH2:12][C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:5]1)#[N:2].N.[H][H]>CO.[Ni].[Mo]>[NH2:2][CH2:1][CH2:3][C@H:4]1[O:9][C:8]([CH3:11])([CH3:10])[O:7][C@@H:6]([CH2:12][C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:5]1

Participants

Conditions

Temperature: 20 °C

Procedure

A solution of (4R-cis)-1,1 dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate (Example 2), 8.2 kg (30.5 mol) in 100 L of methanol containing 15 kg of anhydrous ammonia is reacted with hydrogen gas under 50 pounds per square inch (psi) at 30° C. in the presence of a slurry of 8 kg of Raney nickel doped with 1% molybdenum. After 6 hours, uptake of hydrogen has ceased, the mixture is cooled to 20° C., the atmosphere is vented and exchanged for nitrogen, and the slurry is filtered, concentrated by distillation and distilled under vacuum to give 7.8 kg of 96% pure (4R-cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate as a clear oil; bp 125°-135° C. @0.5 mm Hg. 200 MHz 1H-NMR (CDCl3) 1.0-1.2 (m, 1H), 1.22 (s, 3H), 1.31 (s, 12H), 1.35-1.45 (m, 3H), 2.15 (dd, 1H, J=15.1 Hz, J=6.2 Hz), 2.29 (dd, 1H, J=15.1Hz, J=7.0 Hz), 2.66 (t, 2H, J=6.6 Hz), 3.82 (m, 1H), 4.12 (m, 1H).

Workup

filtrationthe slurry is filtered
concentrationconcentrated by distillation
distillationdistilled under vacuum

Sources & evidence

ORD record: ord-4852493507d04aa2b069bb2020806194
Source dataset: uspto-grants-1992_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05155251

Linked notes

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