The Synthesis of Carbazoles from 3-Vinylindoles with Tetracyanoethylene and Dimethyl Acetylenedicarboxylate

Wayland E Noland, William C. Kuryla, Ronald F. Lange

Research output: Contribution to journalArticle

58 Citations (Scopus)

Abstract

The tricyanovinylation of indole has been extended to substituted indoles, including 1-methylindole, 2-methylindole and 1,2-dimethylindole, giving the corresponding 3-tricyanovinylindoles (Ib-Id) in good yields. Several derivatives of the latter are described. Tricyanovinylation of skatole occurred in the 1-position, giving 3-methyl-1-tricyanovinylindole (Ie) in 77% yield. 3-Tricyanovinylindole (Ia) and l-methyl-3-tricyanovinylindole (Ib), acting as dienes, undergo Diels-Alder reactions with dimethyl acetylenedicarboxylate, resulting in the loss of hydrogen cyanide and forming the corresponding dimethyl 3,4-dicyanocarbazole-l,2-dicarboxylates (X). Saponification of the latter, followed by esterification of the resulting tetraacids with diazomethane, yielded the corresponding tetramethyl carbazole-l,2,3,4-tetracarboxylates (XI). The one derived from indole (XIa) was prepared independently, along with three minor products CXVIII-XX), by the reaction of indole with dimethyl acetylenedicarboxylate in 1:2 molar ratio. The latter reaction probably involves an intermediate 3-vinylindole (XII) which acts as a diene in a Diels-Alder reaction with a second molecule of dimethyl acetylenedicarboxylate. These reactions appear to represent the_ first examples of the 3-vinylindole synthesis of carbazoles. Decarboxylation of the carbazole tetraacids by pyrolysis with soda-lime gave carbazole in both cases, N-demethylation having occurred in the N-methyl case. Since N-methylcarbazole does not demethylate under the same conditions, it is suggested that the N-demethylation occurs by intramolecular nucleophilic displacement (in a 6-membered ring transition state) of the methyl group by the neighboring 1-carboxylate anion.

Original languageEnglish (US)
Pages (from-to)6010-6017
Number of pages8
JournalJournal of the American Chemical Society
Volume81
Issue number22
DOIs
StatePublished - Jan 1 1959

Fingerprint

Carbazoles
Saponification
Cyanides
Esterification
Lime
Pyrolysis
Negative ions
Cycloaddition Reaction
Derivatives
Hydrogen
Molecules
Skatole
Hydrogen Cyanide
Diazomethane
Indoles
Decarboxylation
Anions
carbazole
acetylenedicarboxylic acid dimethyl ester
indole

Cite this

The Synthesis of Carbazoles from 3-Vinylindoles with Tetracyanoethylene and Dimethyl Acetylenedicarboxylate. / Noland, Wayland E; Kuryla, William C.; Lange, Ronald F.

In: Journal of the American Chemical Society, Vol. 81, No. 22, 01.01.1959, p. 6010-6017.

Research output: Contribution to journalArticle

Noland, Wayland E ; Kuryla, William C. ; Lange, Ronald F. / The Synthesis of Carbazoles from 3-Vinylindoles with Tetracyanoethylene and Dimethyl Acetylenedicarboxylate. In: Journal of the American Chemical Society. 1959 ; Vol. 81, No. 22. pp. 6010-6017.
@article{8155a04ecd2a46379bd0be2f168adb87,
title = "The Synthesis of Carbazoles from 3-Vinylindoles with Tetracyanoethylene and Dimethyl Acetylenedicarboxylate",
abstract = "The tricyanovinylation of indole has been extended to substituted indoles, including 1-methylindole, 2-methylindole and 1,2-dimethylindole, giving the corresponding 3-tricyanovinylindoles (Ib-Id) in good yields. Several derivatives of the latter are described. Tricyanovinylation of skatole occurred in the 1-position, giving 3-methyl-1-tricyanovinylindole (Ie) in 77{\%} yield. 3-Tricyanovinylindole (Ia) and l-methyl-3-tricyanovinylindole (Ib), acting as dienes, undergo Diels-Alder reactions with dimethyl acetylenedicarboxylate, resulting in the loss of hydrogen cyanide and forming the corresponding dimethyl 3,4-dicyanocarbazole-l,2-dicarboxylates (X). Saponification of the latter, followed by esterification of the resulting tetraacids with diazomethane, yielded the corresponding tetramethyl carbazole-l,2,3,4-tetracarboxylates (XI). The one derived from indole (XIa) was prepared independently, along with three minor products CXVIII-XX), by the reaction of indole with dimethyl acetylenedicarboxylate in 1:2 molar ratio. The latter reaction probably involves an intermediate 3-vinylindole (XII) which acts as a diene in a Diels-Alder reaction with a second molecule of dimethyl acetylenedicarboxylate. These reactions appear to represent the_ first examples of the 3-vinylindole synthesis of carbazoles. Decarboxylation of the carbazole tetraacids by pyrolysis with soda-lime gave carbazole in both cases, N-demethylation having occurred in the N-methyl case. Since N-methylcarbazole does not demethylate under the same conditions, it is suggested that the N-demethylation occurs by intramolecular nucleophilic displacement (in a 6-membered ring transition state) of the methyl group by the neighboring 1-carboxylate anion.",
author = "Noland, {Wayland E} and Kuryla, {William C.} and Lange, {Ronald F.}",
year = "1959",
month = "1",
day = "1",
doi = "10.1021/ja01531a039",
language = "English (US)",
volume = "81",
pages = "6010--6017",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "22",

}

TY - JOUR

T1 - The Synthesis of Carbazoles from 3-Vinylindoles with Tetracyanoethylene and Dimethyl Acetylenedicarboxylate

AU - Noland, Wayland E

AU - Kuryla, William C.

AU - Lange, Ronald F.

PY - 1959/1/1

Y1 - 1959/1/1

N2 - The tricyanovinylation of indole has been extended to substituted indoles, including 1-methylindole, 2-methylindole and 1,2-dimethylindole, giving the corresponding 3-tricyanovinylindoles (Ib-Id) in good yields. Several derivatives of the latter are described. Tricyanovinylation of skatole occurred in the 1-position, giving 3-methyl-1-tricyanovinylindole (Ie) in 77% yield. 3-Tricyanovinylindole (Ia) and l-methyl-3-tricyanovinylindole (Ib), acting as dienes, undergo Diels-Alder reactions with dimethyl acetylenedicarboxylate, resulting in the loss of hydrogen cyanide and forming the corresponding dimethyl 3,4-dicyanocarbazole-l,2-dicarboxylates (X). Saponification of the latter, followed by esterification of the resulting tetraacids with diazomethane, yielded the corresponding tetramethyl carbazole-l,2,3,4-tetracarboxylates (XI). The one derived from indole (XIa) was prepared independently, along with three minor products CXVIII-XX), by the reaction of indole with dimethyl acetylenedicarboxylate in 1:2 molar ratio. The latter reaction probably involves an intermediate 3-vinylindole (XII) which acts as a diene in a Diels-Alder reaction with a second molecule of dimethyl acetylenedicarboxylate. These reactions appear to represent the_ first examples of the 3-vinylindole synthesis of carbazoles. Decarboxylation of the carbazole tetraacids by pyrolysis with soda-lime gave carbazole in both cases, N-demethylation having occurred in the N-methyl case. Since N-methylcarbazole does not demethylate under the same conditions, it is suggested that the N-demethylation occurs by intramolecular nucleophilic displacement (in a 6-membered ring transition state) of the methyl group by the neighboring 1-carboxylate anion.

AB - The tricyanovinylation of indole has been extended to substituted indoles, including 1-methylindole, 2-methylindole and 1,2-dimethylindole, giving the corresponding 3-tricyanovinylindoles (Ib-Id) in good yields. Several derivatives of the latter are described. Tricyanovinylation of skatole occurred in the 1-position, giving 3-methyl-1-tricyanovinylindole (Ie) in 77% yield. 3-Tricyanovinylindole (Ia) and l-methyl-3-tricyanovinylindole (Ib), acting as dienes, undergo Diels-Alder reactions with dimethyl acetylenedicarboxylate, resulting in the loss of hydrogen cyanide and forming the corresponding dimethyl 3,4-dicyanocarbazole-l,2-dicarboxylates (X). Saponification of the latter, followed by esterification of the resulting tetraacids with diazomethane, yielded the corresponding tetramethyl carbazole-l,2,3,4-tetracarboxylates (XI). The one derived from indole (XIa) was prepared independently, along with three minor products CXVIII-XX), by the reaction of indole with dimethyl acetylenedicarboxylate in 1:2 molar ratio. The latter reaction probably involves an intermediate 3-vinylindole (XII) which acts as a diene in a Diels-Alder reaction with a second molecule of dimethyl acetylenedicarboxylate. These reactions appear to represent the_ first examples of the 3-vinylindole synthesis of carbazoles. Decarboxylation of the carbazole tetraacids by pyrolysis with soda-lime gave carbazole in both cases, N-demethylation having occurred in the N-methyl case. Since N-methylcarbazole does not demethylate under the same conditions, it is suggested that the N-demethylation occurs by intramolecular nucleophilic displacement (in a 6-membered ring transition state) of the methyl group by the neighboring 1-carboxylate anion.

UR - http://www.scopus.com/inward/record.url?scp=0000906575&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000906575&partnerID=8YFLogxK

U2 - 10.1021/ja01531a039

DO - 10.1021/ja01531a039

M3 - Article

AN - SCOPUS:0000906575

VL - 81

SP - 6010

EP - 6017

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 22

ER -