88802-05-5Relevant academic research and scientific papers
Multiple Structure-Reactivity Relationships for a Menschutkin-type SN2 Reaction
Yoh, Soo-Dong,Tsuno, Yuho,Fujio, Mizue,Sawada, Masami,Yukawa, Yasuhide
, p. 7 - 14 (2007/10/02)
The mechanism of nucleophilic displacement was studied by using three variable systems of ρX, ρY and ρZ obtained from the change of substituents X, Y and Z for the reaction of (Z)-substituted benzyl (X)-benzenesulphonates with (Y)-substituted N,N-dimethylanilines in aceton at 35 deg C.The coefficient of the interaction term, ρXY, has a value of 0.21 which means that bond-making and -breaking are concerted in the SN2 transition state.In the range Z = H to p-NO2, in which the SN2 mechanism is predicted to be dominant, the ρZY value is very large, 0.5, which means that the interaction between Z and Y is very large. ρZX is ca. 0.06 which means that the interaction is small between X and Z.In contrast, in the range Z = H to p-Me, in which the SN1 mechanism is dominant, the ρZY value is nearly zero, indicating no interaction between Z and Y.Changes of substituent effect and interaction terms, ρXY, ρYZ and ρZX are useful tools for distinguishing wrong reaction mechanisms.
Kinetic Isotope Effects in the Menschutkin-Type Reaction of Benzyl Benezenesulfonates with N,N-Dimethylanilines. Variation in the Transition-State Structure
Ando, Takashi,Tanabe, Hiroshi,Yamataka, Hiroshi
, p. 2084 - 2088 (2007/10/02)
Primary carbon-14 and secondary α-tritium isotope effects were measured for the Menschutkin-type reaction of m-bromobenzyl-methylene-14C X-substituted benzenesulfonates with Y-substituted N,N-dimethylanilines in acetone at 35 deg C (eq 1; Z=m-Br).The large carbon-14 (12k/14k = 1.117-1.151) and small α-tritium (Hk/Tk = 1.026-1.041) isotope effetcs were consistent with the SN2 mechanism of the reaction.A monotonous trend was observed when the carbon isotope effects were plotted against the relative rates for varied Xs and a fixed Y (p-CH3), while a bell shape was observed for varied Xs and a fixed (p-Cl).Comparison of the results with those obtained for the unsubstituted benzyl esters indicated that the substitution on the benzyl moiety with the electron-withdrawing m-Br group made the transition state more product-like.Smaller α-tritium isotope effects for the m-Br series than those for the unsubstituted series verified tighter transition states for the former.The variation in the three-centered SN2 transition states caused by the substituents on the leaving group, the nucleophile as well as the benzyl moiety, is discussed in terms of Thornton's rules and described on a potential energy map.
