화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Applied Chemistry for Engineering, Vol.23, No.2, 241-246, April, 2012
Export Citation
크롬(VI)-헤테로고리 착물(2,2'-Bipyridinium Dichromate)에 의한 치환 벤질 알코올류의 산화반응에 대한 속도론적 연구
Kinetic Study on the Oxidation Reaction of Substituted Benzyl Alcohols by Cr(VI)-Heterocyclic Complex (2,2'-Bipyridinium Dichromate)
김영식†, 박영조
  • 강원대학교 화학공학과
Young Sik Kim†, and Young Cho Park
  • Department of Chemical Engineering, Kangwon National University, Gangwon-do 245-711, Korea
E-mail:
초록
크롬(VI)-헤테로고리 착물(2,2'-bipyridinium dichromate)를 합성하여, 적외선분광광도법(IR), 유도결합 플라즈마(ICP) 등으로 구조를 확인하였다. 여러 가지 용매 하에서 2,2'-bipyridinium dichromate를 이용하여 벤질 알코올의 산화반응을 측정한 결과 유전상수(ε) 값이 큰 용매 순서인 시클로헥센 < 클로로포름 < 아세톤 < N,N-디메틸포름아미드 용매 하에서 높은 산화반응성을 보였다. 산 촉매(H2SO4)를 이용한 DMF 용매 하에서 2,2'-bipyridinium dichromate는 벤질 알코올과 그의 유도체들(p-OCH3, m-CH3, H, m-OCH3, m-Cl, m-NO2)을 효과적으로 산화시켰다. 그리고 전자받개 그룹들은 반응 속도가 감소한 반면에 전자주개 치환체들은 반응속도를 증가시켰다. 또한 Hammett 반응상수(ρ) 값은 -0.66 (303 K)이였다. 그러므로 본 실험에서 알코올의 산화반응 과정은 속도결정단계에서 수소화 전이가 일어나는 메카니즘임을 알 수 있었다.
Cr(VI)-heterocyclic complex (2,2'-bipyridinium dichromate) was synthesized by the reaction between of 2,2'-bipyridine and chromium trioxide in H2O, and characterized by IR and ICP. The oxidation of benzyl alcohol using 2,2'-bipyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant, in the order: cyclohexene < chloroform < acetone < N,N-dimethylformamide. In the presence of DMF solvent with acidic catalyst such as H2SO4 solution, 2,2'-bipyridinium dichromate oxidized the benzyl alcohol and its derivatives (p-OCH3, m-CH3, H, m-OCH3, m-Cl, m-NO2). Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant was -0.66 (303 K). The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.
Keywords:substituted benzyl alcohol;Hammett reaction constant (ρ);hydride ion transfer;rate-determining step
  1. Banerji KK, Bull. Chem. Soc. Japan., 61, 1767 (1988)
  2. Kuo JF, Bull. Chem. Soc. Japan., 64, 3059 (1991)
  3. Mahanti MK, Dey D, J. Org. Chem., 55, 5848 (1990)
  4. Mahanti MK, Bull. Korean Chem. Soc., 4, 120 (1983)
  5. Panigrahi GP, Bull. Korean Chem. Soc., 13, 547 (1992)
  6. Mahanti MK, Kuotsu B, Tiewsoh E, J. Org. Chem., 61, 8875 (1996)
  7. Davis HB, Sheets RM, Pandler WW, Heterocycles., 22, 2029 (1984)
  8. Pressprich MR, Willett RD, Davis HB, Inorg. Chem., 27, 260 (1988)
  9. Cho MH, Kim JH, Park HB, J. Korean Chem. Soc., 33, 366 (1989)
  10. Yadav GD, Haldavanekar BV, J. Phys. Chem. A, 101(1), 36 (1997)
  11. Mahanti MK, Bull. Chem. Soc. Japan., 67, 2320 (1994)
  12. Mahanti MK, J. Org. Chem., 58, 4925 (1993)
  13. Koo IS, Kim JS, An SK,, J. Korean Chem, Soc., 43, 527 (1999)
  14. Tayebee R, J. Korean Chem. Soc., 52, 23 (2008)
  15. Sung RY, Choi H, Koo IS, Bull. Korean Chem. Soc., 30, 1579 (1988)
  16. Kim YS, Choi H, Koo IS, Bull. Korean Chem. Soc., 31, 3279 (2010)
  17. Gilliom RD, Introduction to Physical Organic Chemistry,
  18. Breslow R, Organic Reaction Mechanism, Addison-Wesley, 360 (1995)