1樓：HMPA
巧了，我課題組最近在做類Baylis-Hillman反應，我就是負責編機理的那個。。。
盲猜一波類baylis-hillman反應。
不過好像，就最後一步相似。。。
也許會經過連烯中間體，不過，我還是直接寫碳負離子了。
破案了，找到文獻了，文獻上給的是Stevens重排。
It is known that the Stevens rearrangement smoothly occurs with dimethyl- and diethyl(allyl)(3-phenylprop-2-yn-1-yl)ammonium and 1-allyl-1-(3-phenylprop-2-yn-1-yl)piperidinium bromides by the action of powdered potassium hydroxide in the presence of a few drops of methanol [2]. To obtain the target amines, as starting compounds we used dipropyl- and dibutyl(allyl)(3-phenylprop-2-yn-1-yl)ammonium bromides Ia and Ib, 1-allyl-1-(3-phenylprop-2-yn-1- yl)pyrrolidinium bromide (Ic), 4-allyl-4-(3-phenylprop-2-yn-1-yl)morpholinium bromide (Id), diethyl- (allyl)(3-p-tolylprop-2-yn-1-yl)ammonium bromide (IIa), 1-allyl-1-(3-p-tolylprop-2-yn-1-yl)piperidinium bromide (IIb), and diethyl(allyl)(3-m-tolylprop-2-yn1-yl)ammonium bromide (III). In all cases, except for salt IIa, the rearrangement was accompanied by heat evolution.
In the reaction with salt III, the heat evolution was weak; therefore, the reaction mixture was heated for several minutes at 60–70°C to complete the process. As a result, we obtained dipropyl- and dibutyl- (1-allyl-3-phenylprop-2-yn-1-yl)amines IVa and IVb, 1-(1-allyl-3-phenylprop-2-yn-1-yl)pyrrolidine (IVc), 4-(1-allyl-3-phenylprop-2-yn-1-yl)morpholine (IVd), diethyl(1-allyl-3-p-tolylprop-2-yn-1-yl)amine (Va), 1-(1-allyl-3-p-tolylprop-2-yn-1-yl)piperidine (Vb), and diethyl(1-allyl-3-m-tolylprop-2-yn-1-yl)amine (VI) in 64, 52, 60, 74, 55, 52, and 58% yield, respectively (Scheme 1). Comparison of the yields of amines IVa– IVd, Va, Vb, and VI with those of the dialkyl(1-allyl3-arylprop-2-yn-1-yl)amines obtained previously [2]
纏論，請問下面這個圖應該怎麼分析呢？
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請問下面這個比例尺是什麼意思？這種形狀的比例尺是什麼意思？
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請問圖中這個反應怎麼可以達成啊？
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