Quinoline → (Z)-Ethyl cinnamate

Ethyl phenylpropiolate (10.8 g, 0.062 mol) was dissolved in hexane (540 ml), followed by addition of quinoline (11.2 g) and palladium on calcium carbonate (Lindlar catalyst, 3.6 g). The resulting reaction mixture was stirred under hydrogen (1 atm) at room temperature, and the progress of the reaction was monitored closely by GC analysis. The reaction was stopped by displacement of the hydrogen atmosphere with nitrogen once the rate of absorption of hydrogen was observed to decrease abruptly. The resulting mixture was faltered through a pad of diatomaceous earth and the filtrate was dried over Na2SO4. Solvent was removed under reduced pressure. Then the residue was distilled under vacuum (2.5 mm Hg, at 98°-100° C.) to provide 10.08 g of cis-ethyl cinnamate, for a yield of nearly 95%. By GC analysis, this product mixture was found to contain 5.7% over-reduced alkane and 3.5% trans-ethyl cinnamate, but was used without further purification.

1. customThe resulting reaction mixture
2. customThe reaction was stopped by displacement of the hydrogen atmosphere with nitrogen once the rate of absorption of hydrogen
3. dry with materialthe filtrate was dried over Na2SO4
4. customSolvent was removed under reduced pressure
5. distillationThen the residue was distilled under vacuum (2.5 mm Hg, at 98°-100° C.)

ORD record

ord-4ef38cd7c11846bc8abe9a99672ecab0

Source dataset

uspto-grants-1997_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05637739