Neopentane chloro

CHLORO-2-METHYLBUTANE N-METHYLPYRROLIDINE PIPERIDINE tert-BUTYLFORMAMIDE ISOPENTANE NEOPENTANE n-PENTANE... 

Propane and cyclopentane give isopropyl chloride and cyclopentyl chloride, respectively, whereas isobutane is transformed to ferf-butyl chloride under the same reaction conditions (yields are 69%, 74%, and 76%, respectively). Neopentane undergoes isomerization to yield 2-chloro-2-butane (88%). When saturated, hydrocarbons were allowed to react with methylene bromide and SbF5 bromoalkanes were obtained in comparable yields (64-75%). Formation of the halogenated product can be best explained by the mechanistic pathway (I) depicted in Scheme 5.55. Since SbF5 always contains some HF, mechanism (II) may also contribute to product formation (Scheme 5.55). 

Chlordane is prepared by reacting hexachlorocyclopentadiene (40) formed as the main product in the chlorination of cyclopentadiene (42) with hypochlorite or in the high temperature chlorination (470°C) of pentane, neopentane or cyclopentane with cyclopentadiene (Diels-Alder reaction), and chlorinating the 4,5,6,7,8,8-hexa-chloro-4,7-methano-3a,4,7,7a-tetrahydroindene (chlordene, 43) yielded by this reaction until two additional chlorine atoms are absorbed, obtaining 4,7-methano-... 

Neopentane diol condenses with phosphorus trichloride in a manner analogous to (6.914) to give 2-chloro-5,5 -dimethyl-l,3,2 dioxaphosphinane. This latter compound is converted into the ethoxy derivative by a mixture of ethanol and pyridine, and it is oxidised in benzene solution to the oxychloride. Other reactions of the diol are indicated in the below scheme. 

A general mediod for the synthesis of aryloxy(chloro)neopentylidene-tungsten complexes involves the reaction of WCl4(OAr)2 (OAr = 2,6-disubstituted phenoxide) [20] with 1 equiv or 1.5 equiv of MgNp2(dioxane) (Np=CH2C(CH3)3) [11, 21] (Scheme 1). The reaction proceeds via a double (or triple) kylation of tungsten followed by an a-H abstraction and elimination of neopentane [22]. In the particular case of the 2,6-diphenyl-phenoxide complexes, the activation of m ortho C-H bond in one of the phenyl substituents of the aryloxide ligands leads to the elimination of HCl with the formation of a cyclometalated compound (Scheme 2) [23, 24]. 

Interestingly, the fluoro complex is rather unstable and scavenges chloride from solvent to yield the crystallographically characterized chloro conq)lex. Most recently, Hoffmann and Unfried (33) have reported the quantitative oxidative addition of C6F6 to a 14-electron Pt(0) fragment generated by reductive elimination of neopentane in neat C6p6 (equation 8). 

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