Reactivity of Substituents Attached to the Ring Nitrogen Atom

7 Reactivity of Substituents Attached to the Ring Nitrogen Atom 

An oxidation of the nitroso group in l-nitroso-3-nitroazetidine 122 by nitric acid in trifluoroacetic anhydride led to the synthesis of 1,3-dinitroazetidine 123 (Equation 33) 1998SC3949 , which serves as a substrate for the synthesis of the highly energetic 1,3,3-trinitroazetidine. 

A fluoride ion-induced desilylation of the trimethylsilyl group at A lbisltrimethylsilybmethyllazetidin-S-ols served as a useful method for the preparation of l-methylazetidin-3-ols 1998SL510 . 

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REACTIVITY OF SUBSTITUENTS ATTACHED TO THE RING NITROGEN ATOM... 

REACTIVITY OF SUBSTITUENTS ATTACHED TO THE RING NITROGEN ATOM 2.02.4.1 Alkyl and Substituted Alkyl Groups... 

Very few publications are available on the reactivity of substituents attached to the ring nitrogen and sulfur atoms of thiadiazole. The N-benzyl group in (107) can be removed with AICI3 to give the cyanamide (108) and the antiviral compound (109) on further treatment with base <92MI 410-01 >. 

Reactivity of the Substituents Attached to a Ring Nitrogen Atom. 209... 

There are no reports of reactions of substituents attached to the ring heteroatoms of oxazoles. The oxazole nitrogen atom can be alkylated or acylated to give a reactive oxazolium species that facilitate further transformations of the ring. These reactions are summarized in CHEC-II(1996) <1996CHEC-II(3)261> and further described in Section 4.04.5.2 of this chapter. 

The electron-withdrawal to the cyclic nitrogen atom can be transmitted to the y-position of pyridine (560) (illustrating the principle of vinylogy). Hence, y-substituents have properties similar to those of a-substituents. 3-Substituents in pyridine are not directly conjugated with the heteroatom usually the reactivity is intermediate between that of the same substituent attached to a benzene ring, and that of an a- or y-substituted pyridine. 

Reactivity of the substituents attached to ring nitrogen atom 179... 

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