2-(4-Chlorophenyl)-3-methylbutanoyl chloride → (4-Chlorophenyl)isopropylketene

To a solution of 2.31 g of isopropyl(4-chlorophenyl)acetyl chloride in 10 ml of methylene chloride was added in one portion 1.5 g of triethylamine. After 18 hours, 15 ml of heptane was added to the mixture and the triethylamine hydrochloride was removed by filtration. The filtrate was stripped and 10 ml of heptane was added and the resulting mixture was filtered and stripped to give a yellow residue, which was dissolved in 5 ml heptane for GLC analysis. The resulting solution was distilled through a Bantam-ware short-neck head from an oil bath at 125°-150° C. and head temperature of 110°-100° C. at 0.2-0.05 mm to give 0.95 g of distillate and 0.81 g of gum. The distillate was crystallized twice from 2 volumes of hexane at -80° C. The solid was melted and stripped to about 40° C. at 0.5 mm to give 0.42 g of the desired product as a yellow liquid.

1. customthe triethylamine hydrochloride was removed by filtration
2. addition10 ml of heptane was added
3. filtrationthe resulting mixture was filtered
4. customto give a yellow residue, which
5. distillationThe resulting solution was distilled through a Bantam-ware short-neck head from an oil bath at 125°-150° C.

ORD record

ord-10d117f4500d40a1b24f832f34662622

Source dataset

uspto-grants-1987_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04681947