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mechanism of the cycloaddition reaction

2026-02-17 22:10
2026-02-18 00:09

The cycloaddition reaction was a bimoleral reaction in which the carbon atoms of the end groups of two molecules in a Conjugated System joined together to form a ring. When forming a sigma-bond in the cycloaddition reaction, the carbon atoms of each pair of end groups could be in the same or different faces. If the polyene reagent has a substitution, then the product molecules may have different, recognizable structural characteristics. According to the principle of conservation of molecular orbit, the main way of cycloaddition reaction could be determined: when the sum of the number of carbon atoms in the two reaction molecules was an integral multiple of four, the thermochemical reaction was mainly carried out in the same face-different face or different face-same face way, and the photochemical reaction was mainly carried out in the same face-same face or different face-different face way. When the sum of the number of carbon atoms in the two reaction molecules is an even number that is not an integral multiple of four, the thermochemical reaction is mainly carried out in the same face-same face or different face-different face manner, and the biochemical reaction is mainly carried out in the same face-different face or different face-same face manner. For example, the sum of the number of carbon atoms in the Diels-Alder reaction was 6, which was an even number that was not an integral multiple of four. The thermochemical reaction was mainly carried out in the same face-same face or different face-different face manner. In addition, taking the "cycloaddition/ring-opening" reaction of bicyclo [1.1.0] butanes (BCPs) and triazinane reported by Peng Shiyong's research group of Wuyi University as an example, the cycloaddition followed a step-by-step (3 + 2 + 2) instead of (4 + 3) cycloaddition. It involved the SSN2-like addition of formaldimine and Lewis acid activated BCPs. The possible mechanism was: first, B(C6F5)3 activated 2a to form complex I; then, formaldimine (formed in place from triazinane 1a) and I carried out a N-like addition to form intermediate II; then, it reacted with another formaldimine to form intermediate III; finally, the molecular cycle released the B(C6F5)3 catalyst to form product 3a. Fantasy Realm is equally exciting. Everyone is welcome to click and read it!

Latest Questions

In which novel is the strangest scene where the female lead transmigrated?

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2026-07-03 09:13

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2026-07-03 09:13

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2026-07-03 09:13

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2026-07-03 09:13

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2026-07-03 09:13

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2026-07-03 09:13

Japanese photography cuisine

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2026-07-03 09:12

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The pronunciation of flood dragon was: The novel " Flood Dragon " is equally exciting. Everyone is welcome to click and read it!

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2026-07-03 09:12

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2026-07-03 09:12
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