Alkyl and Cycloalkyl Halides

No Name Melting point. C Boiling point, C S-Alkyl thiuro- mum 1-Naphthyl amide Anilide Alkyl mer- curic Picrate of 2-naph- 2,4-Di- mtro- phenyl 2,4-Di- nitro- phenyl Miscellaneous 

2-Bfs rilloromcthyl)bcBzene (o-Xylylene dichlonde) 54-5 239-41 Oxid — phthalic acid, 200-6 

4-Bia diloroiiiethyl)benzeoe 98-100 240-5 Heating with benzyl alcohol 

No Name Boiling poinl, C d DJ S-Mkyl thmronium picrale 1 Naph thyl amide Anilide Alkyl mercuric halide Picraic of 2-naphlhyl ether 2,4-Diniiro phenyl Ihioether 2,4 DinilrO phenyl sulfone Miscellaneous 

3-Bia(dilonMnctliyl)bciizeae (m-Xylylene dichloride) 32-4 250-5 Diphthalimide deriv, 237 

No Name Boiling point, C S-Mkyl thturonium picrate 1 Naph thyl amide Anilide Alkyl mercunc halide Picratc of 2-naphthyl ether 2,4-l nttro phenyl thioether 2,4-Dinitro- phenyl sulfone 

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Alkyl and cycloalkyl halides react with benzenetellurolate to yield (cyclo)alkyl phenyl telluriums, which are converted to (cyclo)alkyl phenyl tellurium dibromides upon treatment with bromine. Stirring of a mixture of these tellurium dibromides and 0.5 M aqueous sodium hydroxide at 20° resulted in the formation of (cyclo)alkenes5. Alkyl phenyl tellurium oxides were postulated as intermediates that eliminated phenyl tellurium hydroxide. 

Reduction of aryl and alkyl halides. This reaction can be conducted in generally good yield with LiAlHi by a free-radical process initiated by irradiation of di-t-butyl peroxide. The order of reactivity of aryl halides is Arl > ArBr > ArCI > ArF. Alkyl and cycloalkyl halides are reduced efficiently, but vinyl bromides are reduced in only modest yield. 

The stereochemistry of dehydrohalogenation with DBU has been studied by several authors. Wolkoff (82JOC1944) studied in detail the stereochemical consequences of dehydrohalogenation of secondary and tertiary alkyl and cycloalkyl halides with DBU. A comparison of the product distributions obtained in the elimination reactions of alkyl halides with DBU, with weak bases, and with anionic bases indicated that the elimination reactions with DBU very probably follow an E2C-like mechanism. 

The electron affinities of the alkyl and cycloalkyl halides reported in the NIST tables are tabulated and evaluated in Appendix II. The NIST value is returned by a sequential search, using CX, CC1F, or CHX. In some cases two values that differ by more than the uncertainty have been reported so excited-state values can be assigned. Many of the Ea have only been measured by one technique thus, the experimental values could refer to an excited state. 

TABLE V. ORGANIC DERIVATIVES OF HALIDES A) Alkyl and cycloalkyl halides 1. Chlorides a) Liquids (Listed in order of increasing atmospheric b.p.) ... 

Reactions of Alkyl and Cycloalkyl Halides with Sodium or Potassium Cyanide in Dimethyl Sulfoxide ... 

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