合成(±)猫薄荷

1941年在猫薄荷中分离出荆芥内酯(JACS.1941.63.1558),67-80%猫猫会对其起反应
合成路线如下:


(绘图软件:Chemdraw)
Step 1.二氧化硒氧化氧化烯丙基位的C-H得到烯丙醇产物

反应机理

[2,3]σ重排(Ref: J. Org. Chem. 2000 , 65 , 7554., Tetrahedron Lett. 2003 , 44 , 1099.)
image
虽然这试剂是有毒的,但是该反应非它不可,条件也很温和所以经常还是在被使用。如果加入助氧化剂TBHP的话,可以把二氧化硒的使用量减少到催化量。
step1.


操作步骤:

Racemic citronellol (23.4 mL, 128 mmol, 1 eq) was added to a solution of SeO2 (0.855 g, 7.7 mmol, 0.06 eq), salicylic acid (2.13 g, 15.4 mmol, 0.12 eq), and t-BuOOH (70% in H2O, 53 mL, 553 mmol, 4.3 eq) in DCM (40 mL) and the resulting reaction mixture was stirred at rt for 72 h. The reaction mixture was diluted with toluene (100 mL) and the volatiles were removed by rotary evaporation. The residue was diluted with ether (400 mL) and washed with NaOH (10% w/v, 4 × 140 mL) and brine (1 × 120 mL). The organic layer was dried over MgSO4 (anhyd), filtered, and the volatiles were removed by rotary evaporation to yield a clear yellow oil (21.2 g, 95%).
原料香茅醛


Racemic citronellol (23.4 mL, 128 mmol, 1 eq)in DCM (40 mL)

SeO2 (0.855 g, 7.7 mmol, 0.06 eq)& salicylic acid (2.13 g, 15.4 mmol, 0.12 eq)

t-BuOOH (70% in H2O, 53 mL, 553 mmol, 4.3 eq)

The mixture was stirred at r.t. for 72 h

After 3 days,analysis of the reaction mixture by TLC(Hexane:ethyl acetate=5/1)

step 2.戴斯-马丁氧化
the reaction mixture was diluted with toluene (100 mL) and the volatiles were removed by rotary evaporation. The residue was diluted with ether (400 mL) and washed with NaOH (10% w/v, 4 × 140 mL) and brine (1 × 120 mL). The organic layer was dried over MgSO4 (anhyd), filtered, and the volatiles were removed by rotary evaporation to yield a clear yellow oil。Then Dess-Martin periodinane was added to a solution of this product in DCM and the resulting reaction mixture was stirred at 0℃ overnght。

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想起以前看到过的一个

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哈哈,这个我看过
我是这个改良版的方法,第一步产率会高点

哇哦 :c_nb:
不过为什么前面是中文,后面变成英文了的说(发出了门外汉的声音 :c_shounuehuaji:

这是按supporting information写的。直接写的英文

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之前本来打算做这东西的,手头也正好有多余的材料,但是感觉那个香茅醛的味道怪怪的,实在闻不惯,后来扔了就搁置了

手办好评(是不是跑题了 :c_shounuehuaji:

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