Preparation of secondary and tertiary

For the preparation of secondary and tertiary selenoamides, several methods have been used reaction of lithium alkyneselenolates (obtained using metallic selenium) with amines, aromatic diselenoic acid Se-methyl esters with amines or dihalomethane with elemental selenium, NaH and amines (Scheme 83).258 266... 

Sulfenimines are versatile building blocks for the preparation of secondary and tertiary amines. Therefore, fluoroalkylated sulfenimines should be promising building blocks for the preparation of N-fluoroalkylamino compounds. In fact, very recently, trifluoromethylated sulfenimines have been easily prepared in... 

As outlined, electrophilic animation of diorganozincs with A-mono- and A,A-disub-stituted O-benzoylhydroxylamines is a general procedure and an easy route for the preparation of secondary and tertiary amines from diorganozincs. 

The method described is quite general for the preparation of primary bromides. The presence of sulfuric acid would usually be objectionable in the preparation of secondary and tertiary bromides because of the ease of dehydration of the corresponding alcohols. Moreover, these bromides may be obtained in good yields without the use of sulfuric acid. 

ALKYLATION AND REDUCTIVE ALKYLATION PROCEDURES FOR THE PREPARATION OF SECONDARY AND TERTIARY AMINES... 

Helgen, C. Bochet, C. G. Preparation of secondary and tertiary amides under neutral conditions by photochemical acylation of amines. Synlett 2001, 1968—1970. 

Vilsmeier, A., Haack, A. Action of phosphorus halides on alkylformanilides. A new method for the preparation of secondary and tertiary p-alkylaminonobenzaldehydes. Ber. 1927, 60B, 119-122. 

The preparation of chlorides by decarboxylation of carboxylic acids with lead tetraacetate and N-chlorosuccinimide as the chlorine donor in a 5 1 mixture of DM F and glacial acetic acid has been reported [71 a]. The reaction has been applied particularly often to the preparation of secondary and tertiary chlorides when the classic Hunsdiecker reaction gives low yields (Scheme 13.50) [71b]. This reaction proceeds by a radical pafhway. 

For the preparation of secondary and tertiary amines by monoalkylation of, respectively, primary and secondary amines by alkali halides there are as few satisfactory prescriptions in the literature as there are for the reaction with ammonia. The main difficulties have been mentioned above. 

Rieke zinc is useful for the preparation of secondary and tertiary alkyl zinc bromides. The employment of activated zinc deposited on Ti02, which is obtained from reduction of ZnCU by sodium dispersed on TiOj, is another possibility (for sec-R and benzylic bromides). ... 

This reaction is generally useful for the preparation of secondary and tertiary halides. 

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