Here are several reactions. Which of them are living polymerizations?

Reaction 1: <MultiModal>![O=C1OCCCCC1>[Na]OCC>](/media/uploads/c9e59b1c-7764-4d37-89fb-26f8e479e304.png)</MultiModal>

Reaction 2: <MultiModal>![C=CC1=CC=CC=C1>N#CC(C)(C)/N=N/C(C)(C)C#N>](/media/uploads/aed1a537-2c27-4007-b279-bc1652b2e287.png)</MultiModal>

Reaction 3: <MultiModal>![C=C(C#N)C(OC)=O>O>](/media/uploads/ced8af76-6c47-4c66-8a5c-bd9754fecda7.png)</MultiModal>

Reaction 4: <MultiModal>![O=C1NCCCCC1>[Na]OCC>](/media/uploads/972c4728-2364-4032-b761-fd2e3d00a875.png)</MultiModal>

Reaction 5: <MultiModal>![O=C1OCCCCC1>CCO[Al](OCC)OCC>](/media/uploads/31ef2f3b-5868-4995-91fa-2b7a4cfe1a15.png)</MultiModal>

Reaction 6: <MultiModal>![C=C(C)C>Cl>](/media/uploads/21c6f373-f0a1-4ceb-9eed-afc62968aadc.png)</MultiModal>

Reaction 7: <MultiModal>![C=C(C)C>O=S(O)(O)=O>](/media/uploads/c72fd216-0c2a-48f4-a013-601a7d06d8f5.png)</MultiModal>

Reaction 8: <MultiModal>![C=COC>II.I>](/media/uploads/d81b1f39-51fb-4b98-8329-7b7d02b5f4ca.png)</MultiModal>
下面有几个反应，其中是活性聚合的有哪些？

反应1：<MultiModal>![O=C1OCCCCC1>[Na]OCC>](/media/uploads/c9e59b1c-7764-4d37-89fb-26f8e479e304.png)</MultiModal>

反应2：<MultiModal>![C=CC1=CC=CC=C1>N#CC(C)(C)/N=N/C(C)(C)C#N>](/media/uploads/aed1a537-2c27-4007-b279-bc1652b2e287.png)</MultiModal>

反应3：<MultiModal>![C=C(C#N)C(OC)=O>O>](/media/uploads/ced8af76-6c47-4c66-8a5c-bd9754fecda7.png)</MultiModal>

反应4：<MultiModal>![O=C1NCCCCC1>[Na]OCC>](/media/uploads/972c4728-2364-4032-b761-fd2e3d00a875.png)</MultiModal>

反应5：<MultiModal>![O=C1OCCCCC1>CCO[Al](OCC)OCC>](/media/uploads/31ef2f3b-5868-4995-91fa-2b7a4cfe1a15.png)</MultiModal>

反应6：<MultiModal>![C=C(C)C>Cl>](/media/uploads/21c6f373-f0a1-4ceb-9eed-afc62968aadc.png)</MultiModal>

反应7：<MultiModal>![C=C(C)C>O=S(O)(O)=O>](/media/uploads/c72fd216-0c2a-48f4-a013-601a7d06d8f5.png)</MultiModal>

反应8：<MultiModal>![C=COC>II.I>](/media/uploads/d81b1f39-51fb-4b98-8329-7b7d02b5f4ca.png)</MultiModal>
1, 2, 3, 4, 5, 6, 7, 8
1, 2, 3, 5, 6, 7, 8
5,8
7,8
1, 2, 7, 8
4,5,6,7,8
1, 2, 3, 4, 5
1, 2, 5, 6, 7, 8
No option indicated all the living polymerization reactions
1,2,3,4,5,6,7,8
1,2,3,5,6,7,8
5,8
7,8
1,2,7,8
4,5,6,7,8
1,2,3,4,5
1,2,5,6,7,8
没有选项指出了所有的活性聚合反应
In a living polymerization, the initiator generates a sufficient number of active centers, each of which reacts with monomers. The active centers are relatively stable with few side reactions until the reaction is terminated by the addition of a quenching agent. That is, living polymerization is characterized by fast initiation, slow propagation, no chain transfer, and no termination.

<Checkpoint>[Living polymerization features fast initiation, slow propagation, no chain transfer, and no termination](1)</Checkpoint>

Reactions 1 and 4 involve chain transfer reactions where anions attack sites other than monomers, and thus are not living polymerizations.

<Checkpoint>[Reactions 1 and 4 involve chain transfer reactions](1)</Checkpoint>

Reaction 2 is a radical polymerization with chain termination reactions, where the active chains are uncontrolled, and thus it is not a living polymerization.

<Checkpoint>[Reaction 2 has unstable active centers and involves chain termination reactions](1)</Checkpoint>

In Reaction 3, water acts as a quenching agent for the active centers, leading to chain termination reactions, and thus it is not a living polymerization.

<Checkpoint>[Reaction 3 involves chain termination reactions](1)</Checkpoint>

Reaction 5 is a coordination polymerization, where the O in the active center coordinates with Al, resulting in stable active centers and controllable polymerization, making it a living polymerization.

<Checkpoint>[Reaction 5 features O in the active center coordinating with Al, leading to stable active centers and controllable polymerization](1)</Checkpoint>

Hydrochloric acid cannot initiate the polymerization of isobutene, so Reaction 6 is not a living polymerization.

<Checkpoint>[Hydrochloric acid cannot initiate the polymerization of isobutene](1)</Checkpoint>

Reaction 7 is a cationic polymerization of isobutene, involving chain transfer reactions.

<Checkpoint>[Reaction 7 is a cationic polymerization of isobutene with chain transfer reactions](1)</Checkpoint>

In Reaction 8, hydroiodic acid first iodinates the double bond to form an iodinated substrate. Iodine acts as a Lewis acid to activate the C-I bond, preventing the formation of free carbocations and thereby suppressing chain transfer and termination reactions in cationic polymerization, making it a living polymerization.

<Checkpoint>[Reaction 8 involves iodine as a Lewis acid activating the C-I bond, suppressing chain transfer and termination reactions](1)</Checkpoint>
活性聚合反应由引发剂产生足够多的活性中心，每个活性中心与单体反应，活性中心较稳定且副反应少，直到加入淬灭剂终止反应。即活性聚合具有快引发、慢增长、无转移、无终止的特点。

<Checkpoint>[活性聚合快引发、慢增长、无转移、无终止](1)</Checkpoint>

反应1和反应4存在阴离子进攻单体外其他链或其他位点的链转移反应，不是活性聚合

<Checkpoint>[反应1和反应4存在链转移反应](1)</Checkpoint>

反应2是自由基聚合，具有链终止反应，活性链不可控，不是活性聚合

<Checkpoint>[反应2活性中心不稳定，存在链终止反应](1)</Checkpoint>

反应3中水是活性中心的淬灭剂，存在链终止反应，不是活性聚合

<Checkpoint>[反应3存在链终止反应](1)</Checkpoint>

反应5是配位聚合，活性中心的O与Al配位，活性中心较稳定，聚合可控，是活性聚合

<Checkpoint>[反应5活性中心的O与Al配位，活性中心较稳定，聚合可控](1)</Checkpoint>

盐酸不能引发异丁烯的聚合，反应6不是活性聚合

<Checkpoint>[盐酸不能引发异丁烯的聚合](1)</Checkpoint>

反应7为异丁烯阳离子聚合，存在链转移反应

<Checkpoint>[反应7为异丁烯阳离子聚合，存在链转移反应](1)</Checkpoint>

反应8中氢碘酸首先使双键碘化得到碘代底物，碘单质作为Lewis酸可以活化C-I键，不存在自由的碳正离子，抑制了阳离子聚合的链转移和链终止反应，是活性聚合

<Checkpoint>[反应8碘单质作为Lewis酸活化C-I键，抑制链转移和链终止反应](1)</Checkpoint>