반응 #2507839

반응 방정식

chloroenal

NaOH

Phosphorus oxychloride

chloroenal

sodium hydrogen carbonate

1-(3-propoxy-5,6,7,8-tetrahydro-5,5,8,8,-tetramethylnaphthalen-2-yl)ethanone

→

6-ethynyl-1,1,4,4,-tetramethyl-7-propoxy-1,2,3,4-tetrahydronaphthalene

수율 39.0%

용매

dioxane water

dioxane H2O

dimethyl formamide

brine

반응 조건

후처리

1. 1
   workup.STIRRINGwas stirred for 12 hours
2. 2
   추출Ethyl acetate extraction
3. 3
   기타afforded the crude product
4. 4
   workup.STIRRINGthe reaction mixture was stirred for 2 hours
5. 5
   기타to yield an orange reaction solution
6. 6
   온도The reaction solution was cooled to room temperature
7. 7
   추출extracted with EtOAc
8. 8
   건조The organic phase was dried (MgSO4)
9. 9
   여과filtered
10. 10
    농축concentrated
11. 11
    기타to afford an orange oil which
12. 12
    기타was purified by radial chromatography (10:1 hexane:ethyl acetate)

실험 절차

Phosphorus oxychloride (0.234 grams, 0.142 ml, 1.52 mmol) was added dropwise to dimethyl formamide (DMF) (4 ml) at room temperature under a nitrogen atmosphere. The solution was stirred for 30 minutes. The 1-(3-propoxy-5,6,7,8-tetrahydro-5,5,8,8,-tetramethylnaphthalen-2-yl)ethanone was added quickly (in one portion) to the orange solution, the reaction solution was heated to 60° C. and was stirred for 12 hours. The obtained dark brown solution was poured into ice water and the aqueous layer was adjusted to pH 7 with solid sodium hydrogen carbonate. Ethyl acetate extraction afforded the crude product, the chloroenal (6-[1-hydroxy,2-chloro-ethenyl]-1,1,4,4-tetramethyl-7-propoxy-1,2,3,4-tetrahydronaphthalene), 0.128 grams, as an orange/brown oil. A solution of the crude chloroenal in dioxane:water (3:2; 5 ml) was added to a solution of NaOH (0.061 grams, 1.52 mmol) in dioxane: H2O (3:2; 20 ml), at 80° C., and the reaction mixture was stirred for 2 hours, to yield an orange reaction solution. The reaction solution was cooled to room temperature, poured into brine and extracted with EtOAc. The organic phase was dried (MgSO4), filtered, and concentrated to afford an orange oil which was purified by radial chromatography (10:1 hexane:ethyl acetate) to give the product 6-ethynyl-1,1,4,4,-tetramethyl-7-propoxy-1,2,3,4-tetrahydronaphthalene (39%) as a yellow oil [1H-NMR (400 MHz, CDCl3): d 7.38(s, 1H, Ar—H), 6.76(s,1H, Ar—H), 3.98 (t, J=6.6 Hz, 2H, OCH3), 3.19 (s, 1H, CH),1.83 (m, 2H, CH2),1.66 (m, 2H, 2CH2),1.26 (s, 6H, 2CH3),1.23 (s, 6H, 2CH3), 0.93 (t, J=7.4 Hz, 3H, CH3)].

출처