Carbon Dioxide → Rac. 1-benzyloxy-2-methyhept-5-yn-4-ol

Temperature

-50 °C

A mixture of 72.8 ml. (0.146 mole) of 2 M n-butyllithium solution in hexaneand 420 ml. of anhydrous tetrahydrofuran was stirred and cooled to -50° C. while 112 ml. of liquified methylacetylene was added dropwise from a dry ice cooled addition funnel. After the addition was complete, the reaction mixture was allowed to warm to reflux temperature (8° C.) (dry ice condenser) and stirred at this temperature for 1 hour. The white slurry was then cooled to 0° C. and stirred while asolution of 14 g. (0.0728 mole) of rac. 4-benzyloxy-3-methylbutanal in 125 ml. of anhydrous tetrahydrofuran was added dropwise. After stirring at 0° C. for 1 hour, the mixture was slowly warmed to 40° C. and stirred at this temperature for 1 hour whereupon the reaction mixture was treated with saturated aqueous ammonium chloride. The product was isolated by ether extraction and worked up as in Example 1. There was obtained 15.4 g. of crude material which was chromatographed on 400 g. ofsilica gel. Elution with 2:1 parts by volume and 1:1 parts by volume hexane:ether afforded rac. 1-benzyloxy-2-methylhept-5-yn-4-ol as a yellow oil.

1. additionA mixture of 72.8 ml
2. temperaturecooled
3. additionaddition funnel
4. additionAfter the addition
5. temperatureto warm
6. temperatureThe white slurry was then cooled to 0° C.
7. stirringstirred while asolution of 14 g
8. stirringAfter stirring at 0° C. for 1 hour
9. temperaturethe mixture was slowly warmed to 40° C.
10. stirringstirred at this temperature for 1 hour whereupon the reaction mixture
11. customThere was obtained 15.4 g
12. customof crude material which was chromatographed on 400 g
13. washElution with 2:1 parts by volume and 1:1 parts by volume hexane

ORD record

ord-831dc6a19a8e48618ccc36796bfc83bf

Source dataset

uspto-grants-1981_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04277610