니트로벤젠 또는 1,2,4,-트리클로로벤젠 용매중에서 V족 원소의 브롬화물과 유기브롬화물 사이의 브롬교환반응에 관한 연구

Abstract

삼브롬화안티몬과 벤질브롬화물, 파라메칠벤질브롬화물 또는 몇몇 파라-치환된 벤질브롬화물 사이의 브롬교환반응 속도를 니트로벤젠 및 1, 2, 4=트리클로로벤젠 용매중에서 측정하였다.

니트로벤젠 용매중에서의 실험결과 삼브롬화안티몬과 벤질브롬화물 사이의 브롬교환반응 속도는 실시된 농도구역에서 벤질브롬화물에 관하여 1차 이었으며 삼브롬화안티몬에 관하여 농도에 따라 1차에서 2차의 반응차수를 가지고 변하였다. 따라서 이 교환반응의 속도식은 다음과 같이 쓸 수 있다.

Rate=k₃[Org-Br]¹ [SbBr?]??

또 1, 2, 4-트리클로로벤젠을 용매로 했을 때의 결과는 니트로벤젠을 용매로 했을때와 비슷하였다.

파라위치가 치환된 몇몇 벤질브롬화물의 치환체와 삼브롬화안티몬 사이의 브롬교환반응 속도를 비교하여 보았는데 치환기에 따라 반응속도의 비교는 다음과 같았다.

P-CH₃>P-H>P-Cl>P-NO₂

그리고 실험결과에 따라 적절한 브롬교환반응의 메카니즘도 제시하였으며, 활성화에너지, 활성화엔탈피, 활성화엔트로피, 잦음율과 같은 열역학적 성질들도 구하여 보았다.

The rates of the bromine-exchange reaction between antimony(Ⅲ) bromide and benzyl bromide or several para-substituted benzyl bromides in nitrobenzene and 1, 2, 4-trichlorobenzene were determined utilizing antimony (Ⅲ) bromide labeled with radioactive bromine.

The results indicate that the exchange reaction between antimony (Ⅲ) bromide and benzyl bromide is 1st-2nd order with respect to antimony (Ⅲ) bromide and 1st order with respect to organic bromide in each of the two solvents.

Therefore, the rate law can be written as follows.

Rate=k[SbBr₃]?? [Organic bromide]¹

From the result of exchange reaction kinetics, the mechanism of the bromine exchange reaction between antimony (Ⅲ) bromide and organic bromides is proposed. And some thermodynamic properties for the bromine exchange reaction have been determined.

The rates of the bromine exchange reaction between antimony (Ⅲ) bromide and several parasubstituted benzyl bromides have been compared.

The result is as follows.

P-CH₃>P-H>P-Cl>P-NO₂

The rates of the bromine-exchange reaction between antimony(Ⅲ) bromide and benzyl bromide or several para-substituted benzyl bromides in nitrobenzene and 1, 2, 4-trichlorobenzene were determined utilizing antimony (Ⅲ) bromide labeled with radioactive bromine.

The results indicate that the exchange reaction between antimony (Ⅲ) bromide and benzyl bromide is 1st-2nd order with respect to antimony (Ⅲ) bromide and 1st order with respect to organic bromide in each of the two solvents.

Therefore, the rate law can be written as follows.

Rate=k[SbBr₃]?? [Organic bromide]¹

From the result of exchange reaction kinetics, the mechanism of the bromine exchange reaction between antimony (Ⅲ) bromide and organic bromides is proposed. And some thermodynamic properties for the bromine exchange reaction have been determined.

The rates of the bromine exchange reaction between antimony (Ⅲ) bromide and several parasubstituted benzyl bromides have been compared.

The result is as follows.

P-CH₃>P-H>P-Cl>P-NO₂