Alkanes cyclopropane

Of the monocyclic alkanes, cyclopropane has been studied by INS [16]. The work was able to resolve an uncertainty in the assignment by showing that two modes were accidentally degenerate. 

Cyclopropane is one notable exception to the generalization that cyclic and acyclic compounds undergo the same reactions. Although it is an alkane, cyclopropane undergoes electrophilic addition reactions as if it were an alkene. 

The Simmons-Smith reaction has been used with several methylenecyclo-alkanes to give spiro[2,ra] alkanes. Cyclopropanation of (53) is the first stage of a preparation of dispiro[2,2,2,2]deca-4,9-diene (see p. 151), and the tetra-spiro-compound (54 n = 5) may be made in high yield by a similar reaction... 

NBS can also be used to brominate alkanes. For example, cyclopropane, cyclopentane, and cyclohexane give the corresponding bromides when irradiated in a solution of NBS in dichloromethane. Under these conditions, the succinimidyl radical appears to be involved as the hydrogen-abstracting intermediate ... 

To name an alkane in which the carbon atoms form a single chain, we combine a prefix denoting the number of carbon atoms with the suffix -ane (Table 18.1). For example, CH,—CH, (more simply, CH,CH,) is ethane and CH,—CH2—CH, (that is, CH,CH2CH,) is propane. Cyclopropane, C,H6 (15), and cyclohexane, C6H12 (16), are cycloalkanes, alkanes that contain rings of carbon atoms. 

The present procedure for ring expansion has also been applied to l,2-bis(trimethylsilyloxy)bicyclo[n.l.0]alkanes, which are prepared by cyclopropanation of l,2-bis(silyloxy)cycloalkenes. The latter are readily available from acyloin condensations in the presence of chlorotrimethylsilane. " This reaction provides a new route to cyclic 1,3-diketones and macrocyclic compounds containing two 1,3-diketone units in the ring. 

C09-0122. Cyclopropane, C3 Hg, which has three carbon atoms in a ring, is far more reactive than other alkanes. 

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