C Chemical Shifts Revisited

TABLE 7.1 Chemical Shifts for Common Alkanes and Cycloalkanes  

These are in reasonable agreement with the observed values of 8 73.3, 35.0, and 23.4.  

In Chapter 6 we developed an understanding of the relationships between the molecular environment of a hydrogen atom and the chemical shift of its nucleus. Now let us see if the same approach of base values plus substituent parameters [Eq. (6.5b)] will allow us to predict C chemical shifts. Recall from Sections 2.1 and 2.2 that (like H) has a nuclear spin 

Solution Using as a base value the chemical shift of cyclopentane (5 25.6, Table 7.1) and the internal substituent parameters for the -OH group, we calculate  

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