Propargyl bromide → HCID 22150853, compound

4-Bromo-1,1-diethoxy-2-butyne (Reagent L) was prepared according to the procedure of R. Epsystein and S. Marszak, Bull. Soc. Chim. Fr., I, pp. 313-17 (1968). A total of 74.1 g. (0.40 mole) of propargyl bromine, 59.28 g. (0.40 mole) of triethylorthoformate, and 3.2 g. (0.010 mole) of zinc iodide were combined in a reaction flask fitted with a packed distillation column and a stillhead. The mixture was heated to 100°-110° C. and ethanol was removed by slow distillation over 2.5 hours. Hexane (96 ml.) was added as required to maintain the stillhead temperature below 80° C. The pot residue was diluted with 200 ml. methylene chloride, washed with water and brine, dried with magnesium sulfate, filtered, and then distilled. A forerun of ethylorthoformate was collected, followed by the acetal at 50°-77° C./5-10 mm.

1. customfitted with a packed distillation column
2. temperatureThe mixture was heated to 100°-110° C.
3. customethanol was removed by slow distillation over 2.5 hours
4. additionHexane (96 ml.) was added
5. temperatureto maintain the stillhead temperature below 80° C
6. additionThe pot residue was diluted with 200 ml
7. washmethylene chloride, washed with water and brine
8. dry with materialdried with magnesium sulfate
9. filtrationfiltered
10. distillationdistilled
11. customA forerun of ethylorthoformate was collected
12. customfollowed by the acetal at 50°-77° C.

ORD record

ord-275e85e5d3d24f9fbbfade1bca343aa3

Source dataset

uspto-grants-1987_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04703116