In nucleophilic aliphatic substitution

The thenyl chlorides appear to be more reactive in nucleophilic aliphatic substitution than the benzyl analogs. Thus, 2-thenyh chloride gives, in the reaction with sodium cyanide in ethanol, a mixture of ethyl 2-thenyl ether (25% yield) and 2-thenyl cyanide (32% yield), whereas benzyl chloride gives a high 3deld of benzyl cyanide uncontaminated with benzyl ether. When 2-thenyl chloride and benzyl chloride were allowed to compete for a deficiency of sodium amyloxide, 2-thenyl chloride reacted three times faster. In acetone solution 2-thenyl cyanide is obtained smoothl. ... 

In TFE the secondary isotope effect for solvolysis ( h/ d3)s is found to have the value 1.46 and that for Na,Np-rearrangement (kH/kD3)r has the value 1.42 (Szele and Zollinger, 1981). The two isotope effects are similar to the largest values observed in nucleophilic aliphatic substitutions following the DN + AN mechanism (Shiner,... 

There is a special interest in the role of neighboring group participation by sulfinyl groups in nucleophilic aliphatic substitution. Thus Martin and Uebel218 found that trans-4-chlorothiane-S-oxide 36 is solvolyzed (50% v/v aqueous ethanol, 140 °C) 630 times faster than the cis isomer 37. This was attributed to the intervention of 38 for the former. 

Ashby, E. C. Sun, X. Duff J. L. Single-electron transfer in nucleophilic aliphatic substitution. Evidence for single-electron transfer in the reactions of 1-halonorbomanes with various nucleophiles./. Org. Chem. 1994, 59, 1270-1278. 

Despite the simmering debate within the community of physical organic chemists over the scope and importance of electron transfer in nucleophilic aliphatic substitution [356], evidence continues to accumiflate that electron transfer may play a role... 

In nucleophilic aliphatic substitution (Sn2), the intermediate in which carbon is bonded to both the attacking group and the displaced group is considered to be a transition state a structure (VI) containing carbon bonded to five atoms must be... 

Doubly and triply bridged polyoxapolyazaheterophanes developed from cyanuric chloride are available which can complex alkali cations and therefore act as catalysts in nucleophilic aliphatic substitutions under phase-transfer conditions <84JOC4i97>. 

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