Cahn-Prelog-Ingold Rules

II R has higher priority than R in - A the Cahn-Ingold-Prelog rules... 

The Cahn-Ingold-Prelog rules (1956) are used to designate the configuration of each chiral C in a molecule in terms of the symbols R and S. These symbols come from the Latin, R from rectus (right) and S from sinister (left). Once told that the configuration of a chiral C is R or S, a chemist can write the correct projection or Fischer structural formulas. In our statement of the three rules the numerals 1, 2, 3, and 4 are used some chemists use letters a, b, c. and d in their place. 

The Cahn-Ingold-Prelog rules work for inorganic compounds too but coordination complexes often have coordination numbers greater then four and may exhibit helical chirality, for example, denoted A and A (or Pand Min the Cahn-Ingold-Prelog system). The formal condition for chirality is that the molecule should not have an improper axis of rotation (i.e. a rotation + reflection axis, 5n =... 

C-13 nmr. 245/f Cahn-Ingold-Prelog rules. 72 Cannizzaro reaction. 312 Caibaldehyde. 303 Carbenes. 32... 

First, consider the substituents on the right side of the double bond. -Cl ranks higher than -CH2OH by Rule 1 of the Cahn-Ingold-Prelog rules. On the left side of the double bond, -CH2CH3 ranks higher than -CH3... 

Thomson lOVv Click Organic Interactive to practice assigning priorities to groups according to the Cahn-Ingold-Prelog rules. 

In this context, the E- and Z-nomenclature of ester enolates and silyl ketene acetals refers to their geometries where the carbonyl oxygen given highest priority irrespective of priority by CIP Cahn-Ingold-Prelog) rules. 

Called the Cahn-Ingold-Prelog rules after the chemists who proposed them, the sequence rules are as follows ... 

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