Methyl acetoacetate → (E)-6-[2-(2,4-Dichloro-6-(phenylmethoxy)phenyl)ethenyl]-3,4,5,6-tetrahydro-4-hydroxy-2H-pyran-2-one

Temperature

0 °C

Methyl acetoacetate (9.56 g, 82.3 mmole) was added dropwise to a stirred suspension of sodium hydride (50% oil suspension) (3.95 g, 82.3 mmole) in anhydrous tetrahydrofuran at 0° C. under a nitrogen atmosphere. The resulting solution was stirred 15 minutes at 0° C. and then treated with a 1.6M solution (51.5 ml, 82.3 mmole) of n-butyllithium in hexane over 5 minutes. The resulting yellow solution was stirred 15 minutes at 0° C. and then treated with a solution of (E)-2,4-dichloro-6-phenylmethoxycinnamaldehyde (25.3 g, 82.3 mmole) in anhydrous tetrahydrofuran (150 ml). The resulting orange solution was stirred 15 minutes at 0° C. and then quenched by dropwise addition of 12N hydrochloric acid (ca. 20 ml). The reaction mixture was diluted with water (100 ml) and extracted with ether (3×300 ml). The organic extracts were combined, washed with brine (3×100 ml), dried over magnesium sulfate and filtered. The filtrate was evaporated in vacuo leaving the title compound as a yellow oil (34.8 g, 100%): pmr (CDCl3) δ2.75 (2H, d), 3.45 (2H, s), 3.72 (3H, s), 4.71 (H, m), 5.50 (2H, s), 7.37 (5H, s).

1. stirringThe resulting yellow solution was stirred 15 minutes at 0° C.
2. stirringThe resulting orange solution was stirred 15 minutes at 0° C.
3. customquenched by dropwise addition of 12N hydrochloric acid (ca. 20 ml)
4. additionThe reaction mixture was diluted with water (100 ml)
5. extractionextracted with ether (3×300 ml)
6. washwashed with brine (3×100 ml)
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. customThe filtrate was evaporated in vacuo

ORD record

ord-27d915cfb93b49d7a359166ab2fa432f

Source dataset

uspto-grants-1984_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04459422