abs

학술발표회초록보기

초록문의 abstract@kcsnet.or.kr

결제문의 member@kcsnet.or.kr

현재 가능한 작업은 아래와 같습니다.
  • 08월 24일 19시 이후 : 초록수정 불가능, 일정확인 및 검색만 가능

Kinetics and Mechanism of the Reaction of para-Chlorophenyl Aryl Chlorophosphates with Pyridines in Acetonitrile

등록일
2005년 8월 11일 12시 03분 03초
접수번호
0810
발표코드
22P104포 이곳을 클릭하시면 발표코드에 대한 설명을 보실 수 있습니다.
발표시간
토 <발표Ⅳ>
발표형식
포스터
발표분야
물리화학
저자 및
공동저자
B. J. Lumbiny, 김찬경, 이본수, 이해황
인하대학교,
The kinetics and mechanism of the pyridinolysis of p-chlorophenyl aryl chlorophosphates (1) have been carried out in MeCN at 5oC. Lee and coworkers have reported experimentally its (1) aminolysis  (Lee  et al ; Int. J. Chem. Kinet., 2002, 34, 632-637). All the results (rX, rY, bX, rXY, kinetic isotope effects and activation parameters) are consistent with a concerted nucleophilic substitution mechanism. The second-order rate constant for substituents at substrate, Y = H,  p-CH3, p-CH3O were observed for this reaction. The rates are found faster for the pyridinolysis than its aminolysis . bX values are smaller in this work (1.14~1.17) than .the aminolysis (1.43-1.49) indicating less degree of bond formation in TS during pyridinolysis. rX (-5.72 ~ -5.80) supports +ve charge development in reaction center alike aminolysis, rX (-4.04 ~ -4.24). Relatively low ∆H¹ (2.5−4.7 Kcal mol-1) and large negative ∆S¹ values (-49~ -54 cal mol-1K-1) are within the typical range of SN2 reaction. Our interest is comparative mechanistic investigation changing nucleophile from primary to tertiary amine.

상단으로