Synthesis and thermal decomposition of N,N-dialkoxyamides

Digianantonio, Katherine M; Glover, Stephen; Johns, Jennifer; Rosser, Adam Andrew

doi:10.1039/c1ob00008j

Author(s)

Digianantonio, Katherine M

Glover, Stephen

Johns, Jennifer

Rosser, Adam Andrew

Publication Date

2011

Abstract

N,N-Dialkoxyamides 1c, a virtually unstudied member of the new class of anomeric amides, amides bearing two electronegative atoms at nitrogen, have been synthesised in useful yields directly from hydroxamic esters using phenyliodine(III)bis(trifluoroacetate) (PIFA). Infrared carbonyl stretch frequencies and carbonyl ¹³C NMR properties have been reported, which support strong inhibition of amide resonance in these amides. Their thermal decomposition reactions in mesitylene at 155°C proceed by homolysis to form alkoxyamidyl and alkoxyl free radicals in preference to HERON rearrangements to esters. The reactions follow first-order kinetics and for a series of N,N-dimethoxy-4-substituted benzamides, activation energies of 125–135 kJ mol⁻¹ have been determined together with weakly negative entropies of activation.

Citation

Organic & Biomolecular Chemistry, 9(11), p. 4116-4126

ISSN

1477-0539

1477-0520

Link

https://hdl.handle.net/1959.11/8299

Language

en

Publisher

Royal Society of Chemistry

Title

Synthesis and thermal decomposition of N,N-dialkoxyamides

Type of document

Journal Article

Entity Type

Publication

Author(s)	Digianantonio, Katherine M Glover, Stephen Johns, Jennifer Rosser, Adam Andrew
Publication Date	2011
Abstract	N,N-Dialkoxyamides 1c, a virtually unstudied member of the new class of anomeric amides, amides bearing two electronegative atoms at nitrogen, have been synthesised in useful yields directly from hydroxamic esters using phenyliodine(III)bis(trifluoroacetate) (PIFA). Infrared carbonyl stretch frequencies and carbonyl ¹³C NMR properties have been reported, which support strong inhibition of amide resonance in these amides. Their thermal decomposition reactions in mesitylene at 155°C proceed by homolysis to form alkoxyamidyl and alkoxyl free radicals in preference to HERON rearrangements to esters. The reactions follow first-order kinetics and for a series of N,N-dimethoxy-4-substituted benzamides, activation energies of 125–135 kJ mol⁻¹ have been determined together with weakly negative entropies of activation.
Citation	Organic & Biomolecular Chemistry, 9(11), p. 4116-4126
ISSN	1477-0539 1477-0520
Link	https://hdl.handle.net/1959.11/8299
Language	en
Publisher	Royal Society of Chemistry
Title	Synthesis and thermal decomposition of N,N-dialkoxyamides
Type of document	Journal Article
Entity Type	Publication

Synthesis and thermal decomposition of N,N-dialkoxyamides

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