Acetic Anhydride → 6-Heptenoic acid

Temperature

255 °C

In a procedure similar to example 3, a mixture of suberic acid (20.0 g, 0.115 mol), acetic anhydride (11.7 g, 0.115 mol) , and chlorocarbonyl bis(dimethylphenylphospine)rhodium (0.509 g, 0.00115 mol) was heated under reduced pressure (100 torr) using an oil bath maintained at 255° C. and the product collected as it distilled from the reactor. The material removed was continuously replaced with a mixture of suberic acid and acetic anhydride (1:1 molar mixture; a total of 90.0 g of suberic acid was used in the feed mixture) in a rate that maintained the initial level of the reactor contents throughout the course of the entire reaction. The formation of product ceased after about 90 minutes of reaction time. The distillate product collected was fractionally distilled to provide 54.1 g of 6-heptenoic acid (bp 95°-100° C./10 torr) which was found by GC analysis to be >98% of the α-olefin. This amount of product corresponds to a catalyst TON of 368. Considering the amount of unreacted suberic acid containing residue recovered in the distillation pot (19.6 g), the isolated yield of 6-heptenoic acid relative to the suberic acid in the feed mixture was nearly quantitative.

1. temperaturewas heated under reduced pressure (100 torr)
2. customthe product collected as it
3. distillationdistilled from the reactor
4. customThe material removed
5. additionwas continuously replaced with a mixture of suberic acid and acetic anhydride (1
6. temperaturethat maintained the initial level of the reactor contents
7. customthroughout the course of the entire reaction
8. customThe formation of product ceased after about 90 minutes of reaction time
9. distillationThe distillate product collected
10. distillationwas fractionally distilled

ORD record

ord-9e11c33654ff4317a73f6402cdf8cfb6

Source dataset

uspto-grants-1991_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05077447