Isobutylene → isopropyl (R)-2-hydroxy-4-methyl-4-pentenoate

Temperature

-70 °C

A solution of an (R)-binaphthol-dichlorotitanium complex which had been prepared in the same manner as in Example 1 was cooled to -70° C., into which was bubbled 0.56 g (10 mmoles) of 2-methyl-l-propene, followed by adding thereto 116 mg (1 mmole) of isopropyl glyoxylate. Subsequently, the mixture was reacted at -30° C. for 15 hours. Then, 10 ml of an aqueous sodium hydrogen carbonate solution was added to terminate the reaction. The reaction mixture was filtered through Celite and extracted with two 20 ml portions of diethyl ether and two 20 ml portions of ethyl acetate, and the extract was dried over anhydrous magnesium sulfate. Thereafter, the solvents were distilled off, and the residue was purified by means of silica gel column chromatography to obtain 0.13 g of isopropyl (R)-2-hydroxy-4-methyl-4-pentenoate. The yield was 78%.

1. customA solution of an (R)-binaphthol-dichlorotitanium complex which had been prepared in the same manner as in Example 1
2. additionby adding
3. customSubsequently, the mixture was reacted at -30° C. for 15 hours
4. customto terminate
5. customthe reaction
6. filtrationThe reaction mixture was filtered through Celite
7. extractionextracted with two 20 ml portions of diethyl ether and two 20 ml portions of ethyl acetate
8. dry with materialthe extract was dried over anhydrous magnesium sulfate
9. distillationThereafter, the solvents were distilled off
10. customthe residue was purified by means of silica gel column chromatography

ORD record

ord-69bb6141c6724a00a8403444ce5a25a5

Source dataset

uspto-grants-1990_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04965398