Hydrochloric Acid → tert-Butyl propiolate

Reaction equation

[C:1]([O:5][C:6](=[O:33])NC(CC1C=C(F)C=C(F)C=1)C(O)CNC1(C2C=CC=C(C#C)C=2)CC1)([CH3:4])([CH3:3])[CH3:2].Cl.CO.O1CCO[CH2:39][CH2:38]1>>[C:6]([C:38]#[CH:39])([O:5][C:1]([CH3:2])([CH3:3])[CH3:4])=[O:33]

Participants

Reactant 4

HCID 313Hydrochloric Acid

HCID 887Methanol

HCID 312751,4-Dioxane

HCID 21062898[1-(3,5-Difluorobenzyl)-3-[1-(3-ethynylphenyl)cyclopropylamino]-2-hydroxypropyl]-carbamic acid tert-butyl ester

Product 1

HCID 543038tert-Butyl propiolateYield 106%

Procedure

[1-(3,5-difluorobenzyl)-3-[1-(3-ethynylphenyl)cyclopropylamino]-2-hydroxypropyl]-carbamic acid tert-butyl ester (2.34 g, 5.13 mmol) was treated with 4N HCl in dioxane (15.8 mL, 63.3. mmol). The resulting heterogeneous mixture was treated with methanol (10 mL) whereupon it became homogeneous over 30 min. The volatiles were evaporated in vacuo. Dioxane (20 mL) was added and the mixture was evaporated in vacuo to produce a white solid (2.33 g, 106%).