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In nucleophilic aliphatic

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. ... [Pg.88]

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,... [Pg.174]

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. [Pg.530]

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. [Pg.125]

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... [Pg.910]

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... [Pg.829]

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>. [Pg.634]


See other pages where In nucleophilic aliphatic is mentioned: [Pg.178]    [Pg.47]    [Pg.514]    [Pg.542]    [Pg.911]    [Pg.425]    [Pg.44]   


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