تفاعل #2507839

معادلة التفاعل

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

المردود 39.0%

المذيبات

dioxane water

dioxane H2O

dimethyl formamide

brine

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGwas stirred for 12 hours
2. 2
   استخلاصEthyl acetate extraction
3. 3
   أخرىafforded the crude product
4. 4
   workup.STIRRINGthe reaction mixture was stirred for 2 hours
5. 5
   أخرىto yield an orange reaction solution
6. 6
   درجة الحرارةThe reaction solution was cooled to room temperature
7. 7
   استخلاصextracted with EtOAc
8. 8
   تجفيفThe organic phase was dried (MgSO4)
9. 9
   ترشيحfiltered
10. 10
    تركيزconcentrated
11. 11
    أخرىto afford an orange oil which
12. 12
    أخرىwas purified by radial chromatography (10:1 hexane:ethyl acetate)

الإجراء التجريبي

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)].

المصدر