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These spectra are often called carbon magnetic resonance (CMR) spectra or 13C NMR spectra. In some important ways 13C spectra are usually les complex and easier to interpret than proton (1H) NMR spectra

There is a group of compounds in which carbon forms only two bonds. These neutral divalent carbon compounds are called carbenes. Most carbenes are highly unstable compounds that are capable of only fleeting existence. Soon after carbenes are formed they usually react with another molecule

In the addition of HX to an unsymmetrically substituted alkene, the hydrogen atom adds to the carbon atom of the double bond that already has the greater number of hydrogen atoms and that the X group adds to the carbon having more alkyl substituents. Markovnikov’s rule can be restated by saying that, in the addition of HX to an alkene, the more stable carbocation intermediate is formed

1. The experimental conditions — temperature and acid concentration — that are required to being about dehydration are closely related to the structure of the individual alcohol. The relative ease with which alcohols undergo dehydration is in the following order:

SN2 reactions are highly useful in organic synthesis because they enable use to convert one functional group into another —— functional group transformation (functional group interconversion)

The C—X bond of alkyl halides is polarized. The carbon atom bears a partial positive charge, The halogen atom a partial negative charge