Acetate → HCID 13194923, compound

Participants

Reaction Steps

To the crude alcohol from Step (D) supra., there is added 2.34 kg. (29.6 moles) of dry pyridine. Under a blanket of nitrogen gas, 6 kg. (59.2 moles) of acetic anhydride is added at room temperature over a 6 hour period. After stirring several additional hours, a sample is pulled and analyzed on a 6' carbowax column for loss of alcohol and appearance of the desired acetate. After completion of the reaction, the crude product is transferred to a distillation apparatus where the excess acetic anhydride and residual pyridine are removed under vacuum. Finally, the product is flash distilled through a thin film evaporator, the first pass removing residual lights and unreacted 11-chloro-1-undecyne from Step (D), supra., and the second pass to flash the product off higher boiling residues at 170° C./3 mm Hg. This yields 15.3 kg. (53.8 moles) of the acetate which is sufficiently pure to carry on to the next step (yield is 55.7% based on 11-chloro-1-undecyne in Step (D) supra.).

Provenance & Evidence