1.2- Dichloroalkanes

C with low conversion (10—15%) to limit dichloroalkane and trichloroalkane formation. Unreacted paraffin is recycled after distillation and the predominant monochloroalkane is dehydrochlorinated at 300°C over a catalyst such as nickel acetate [373-02-4]. The product is a linear, random, primarily internal olefin. 

A solution of sample in carbon tetrachloromethane is injected directly into the column and alkane- and monochloroalkanesulfonyl chloride determined as chloroalkane and dichloroalkane, respectively. 

Wischnak C, EE Lbffler, J Li, JW Urbance, R Muller (1998) Pseudomonas sp. strain 273, an aerobic a,co-dichloroalkane-degrading bacterium. Appl Environ Microbiol 64 3507-3511. 

The synthesis of polysulfide elastomers involves the use of a small amount of trichloroalkane in addition to dichloroalkane and sodium sulfide in order to form a branched polymer. The prepolymer is treated with a mixture of sodium hydrosulfide and sodium sulfite followed by acidification to convert all end-groups to thiol groups. Further polymerization and crosslinking is achieved by oxidative coupling of the thiol end-groups by treatment with lead dioxide, p-quinone dioxime, or other oxidizing agent... 

Cyclohexane [aluminum chloride catalyzed reduction of a dichloroalkane], hydrocarbon, 121... 

Distannacycloalkanes of the type 42 can be prepared analogously from 1, o>-dichloroalkanes and triorganotinsodium compounds124 ... 

The w-chloroalkyldiphenylphosphines (11) have been prepared by the reaction of equimolar quantities of sodium diphenylphosphide with aco-dichloroalkanes. Whereas the phosphine (11 n = 3) can be converted into the Grignard reagent (12), which reacts with dimethylchlorophosphine to form the unsymmetrical diphosphine (13), the Grignard reagent (14) undergoes a -elimination reaction to regenerate diphenylphosphide ion.13... 

Chlorination of olefins has also been achieved with SbCls in chlorinated solvents, which gives with mono-olefins vicinal dichloroalkanes by a syn addition. A concerted mechanism was initially proposed68 to rationalize this stereochemical behavior and the unexpectedly large amount of c -l,4-dichloro-2-butene found in the reaction of butadiene. In this case, however, because of orbital symmetry control it has been suggested that the addition occurs in an antarafacial direction69. 

Hydrogen bromide, trimethylsilyl bromide and acetyl bromide have all been proven to be suitable bromide transfer agents [e.g. 12, 13]. Tetra-n-butylammonium salts catalyse the interconversion of dichloroalkanes into bromochloroalkanes and chloroiodoalkanes upon reaction with an excess of bromo- and iodobutane, respectively [14]. Similarly, mixed bromochloromethanes are obtained from the reaction of dibromochloromethane with benzyltriethylammonium chloride under basic conditions [15]. 

In an analogous manner to the bromination reactions (2.3.6), dichloroalkanes are obtained from alkenes in moderate yields ( 50%), when tetra-n-butylammonium tetrachloroiodate is used in stoichiometric quantities [9]. The reaction is normally conducted in the dark (Table 2.15). 

Method B The chloroalkane or a,w-dichloroalkane (0.1 mol) and HC02Na (13.6 g, 0.2 mol for the chloroalkane, 27.2 g, 0.4 mol for the a,co-dichloroalkane) are stirred with TBA-Br (1.61 g, 5 mmol) until the reaction is complete (Table 3.16). H20 (10 ml) is added to the cooled mixture. The organic phase is separated, dried (MgS04), and fractionally distilled to yield the formate ester. When aqueous NaOH (50%, 4.5 ml) is added dropwise over 30 min to the vigorously stirred reaction mixture, the alcohol (diol) is formed, which can be isolated by extraction from the reaction mixture with butanone (2 x 20 ml) and fractional distillation. 

Alkenes react with nitryl chloride to give jS-nitroalkyl chlorides, jS-chloroalkyl nitrites and vic-dichloroalkane products. Nitryl chloride reacts with enol esters to give o -nitroketones. ... 

POLYHYDROGEN FLUORIDE REAGENT 1-FLUORO-ADAMANTANE. Dichloroalkane synthesis is shown in cis-DI-CHLOROALKANES FROM EPOXIDES cis-1,2-DICHLORO-CYCLOHEXANE. Nitrile functionality can be introduced from a ketone, as in NITRILES FROM KETONES CYCLOHEXANENITRILE, or from a reactive diene, as shown in 2,3-DICYANOBUTADIENE AS A REACTIVE INTERMEDIATE BY in situ GENERATION FROM 1,2-DICYANO CYCLOBUTENE 2,3-DICYANO-1,4,4a,9a -TETRAHYDRO-FLUORENE. 

During slow thermal chlorination, elimination of HC1 from the monochloride with the resultant formation of an alkene followed by chlorine addition may be the dominant route to yield dichloroalkanes. This mechanism, however, is negligible in rapid thermal or photochemical reactions. 

The phosphorus macrocycles are made via template condensation of coordinated polyphosphine ligands and a dibromoalkane (equation 8).60 A more recently reported method involves a template-assisted single-stage ring closure (equation 9).61 The arsenic donor macrocycles are synthesized by reacting lithiated polyarsanes with a dichloroalkane (equation 10).62... 

One-pot multiple reductive lithiations34 are in fact surprisingly easy to make with lithium and catalytic DBB, providing the electrophile is available in situ. Dichloroalkanes will react twice with carbonyl electrophiles (23), and even CC14 will give a tetrasilylated product 24 in 80% yield.3536... 

Upon pyrolyses, bis[2-chloroalkyl] tellurium dichlorides, obtained from tellurium tetrachloride and propene or 1-butene, yielded v/r.-dichloroalkanes among other products1-3. 

Recently, the reactions of both gera-dichloroalkanes (213, Hlg-Cl) and vinyl chlorides (220, Hlg-Cl) with nitriles were reported. These reactions proceed via the highly active chlorocarbenium intermediates 226. 

Adds to alkynes to yield either chloroalkenes or 1,1-dichloroalkanes (Section 8.3). 

The stability of cr-complexes 2 and their easy formation are substantially governed by the nature of the counter anion. Thus, in HF solution, thiophene and alkylthiophenes form cations stable at temperatures below —40 °C, in HF—BF3 the same cations are stable up to —20 °C and 2,5-dimethyl-2H-thiophenium ion, generated in HF—SbFs is sufficiently stable even at -1-60 °C (66RTC1072). The high stability of 2H-thiophenium ions formed by protonation in the presence of AICI3 in dichloroalkanes as solvents (75ZOR424) is undoubtedly caused by the AICI4 counterions as well as by favorable solvation conditions. The stability of thiophenium ions is mainly caused by their peculiar structure. 

The reaction of oximes with elemental chlorine is known. In the presence of a Lewis acid, gc / i-dichloroalkanes 7 are obtained. ... 

Polyarsa macrocycles can be made by the reaction of lithiated polyarsanes with a dichloroalkane (Scheme... 

Alkynes. Primary alkyl halides react with dichloromethyllithium in the presence of HMPT (1 equiv.) to form homologated 1,1-dichloroalkanes in 60-90% yield. Several methods have been used for dehydrochlorination of the products. A new method is the reaction with 3 equiv. of n-butyllithium to form a lithium... 

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