Imines Wolff—Kishner reduction

Deuterium labeling of C-18 has also been accomplished by an alternate procedure adapted from the Nagata steroid synthesis. During the course of the total synthesis of pregnanolone, thevC-18 function is introduced in the form of a nitrile group. Reduction of this function in intermediate (247) with lithium aluminum deuteride leads to a deuterated imine (248), which upon Wolff-Kishner reduction and acid-catalyzed hydrolysis... 

Also other reaction types have been dealt with in CHEC(1984) and CHEC-II(19%) like reduction to alcohols (e.g., sodium borohydride), Wolff Kishner reduction, nucleophilic addition via reaction with Grignard reagents or organo-lithium compounds, and formation of imine type functional groups (e.g., hydrazones). New examples are the reaction of... 

Aldehydes and ketones react with primary amines to form imines and with secondary amines to form enamines. The mechanisms are the same, except for the site from which a proton is lost in the last step of the reaction. Imine and enamine formation are reversible imines and enamines are hydrolyzed under acidic conditions back to the carbonyl compound and amine. A pH-rate profile is a plot of the observed rate constant as a function of the pH of the reaction mixture. Hydroxide ion and heat differentiate the Wolff-Kishner reduction from ordinary hydrazone formation. 

A.8 IMINES AND RELATED FUNCTIONAL GROUPS THE WOLFF-KISHNER REDUCTION AND THE SHAPIRO REACTION... 

The synthetic uses of hydrazones and oximes for carbon-bond formation differ little from those of imines as their anions represent enolate equivalents except for certain methods that have been developed for asymmetric induction. Conversely, the formal replacement of the carbon substituent of imines by a heteroatom (nitrogen for hydrazones and oxygen for imines) opens reaction pathways such as the Beckmann rearrangement of oximes and the Wolff-Kishner and Shapiro reductions of hydrazones that have no analogy in the chemistry of imines. 

---