Cyclobutanecarboxylic acid, 3-ethyl- → 1-(3-Ethylcyclobutyl)ethanone

A solution of 6.61 g of 3-ethylcyclobutane-1-carboxylic acid, in 52 ml of distilled ether was stirred under argon at 0°. Methyllithium (85.0 ml of a 1.53 M solution in ether) was added dropwise over a 30 minute period. The reaction mixture was stirred for three hours at 25°, then quenched with 7.3 water-methanol. The layers were separated, and the aqueous layer extracted with ether. The combined organic layers were washed with brine, dried, filtered and the solvents evaporated in vacuo. The resultant oil was distilled (aspirator vacuum) to afford 5.5 g of 1-acetyl-3-ethylcyclobutane, as a clear oil (bp 64°-67°). The material had the following spectral characteristics: nmr (CDCl3) δ 0.80 and 0.82 (3H total, pair of t, each J=7.0 Hz), 1.10 and 1.12 (ca. 1.5H total, pair of s, side product 1-[2-hydroxy-prop-2-yl]-3-ethylcyclobutane), 1.0-2.4 (7 H, m), 2.07 and 2.09 (3H total, pair of s) and 2.7-3.5 ppm (1H, m); ir (CHCl3) 935, 1175, 1370, 1460, 1705, 2870, 2930 and 2970 cm-1, also small 3200-3600 broad and 3600 cm-1 for the side product noted above.

1. customquenched with 7.3 water-methanol
2. customThe layers were separated
3. extractionthe aqueous layer extracted with ether
4. washThe combined organic layers were washed with brine
5. customdried
6. filtrationfiltered
7. customthe solvents evaporated in vacuo
8. distillationThe resultant oil was distilled (aspirator vacuum)

ORDレコード

ord-d455ee066f7f494084a5e26a1c625507

出典データセット

uspto-grants-1981_06

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US04275224