e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521

Synthesis of 2 H-indazoles by the [3+ 2] dipolar cycloaddition of sydnones with arynes

Y Fang, C Wu, RC Larock, F Shi

Index: Fang, Yuesi; Wu, Chunrui; Larock, Richard C.; Shi, Feng Journal of Organic Chemistry, 2011 , vol. 76, # 21 p. 8840 - 8851

Full Text: HTML

Citation Number: 44

Abstract

A rapid and efficient synthesis of 2 H-indazoles has been developed using a [3+ 2] dipolar cycloaddition of sydnones and arynes. A series of 2 H-indazoles have been prepared in good to excellent yields using this protocol, and subsequent Pd-catalyzed coupling reactions can be applied to the halogenated products to generate a structurally diverse library of indazoles.

p-Anisidine Structure

~%

(1-(4-methoxyphenyl)-2-oxohydrazino)acetic acid Structure

(1-(4-methoxyph...

ethyl 2-[(4-methoxyphenyl)amino]acetate Structure

ethyl 2-[(4-met...

~%

(1-(4-methoxyphenyl)-2-oxohydrazino)acetic acid Structure

(1-(4-methoxyph...

3-Methylsydnone Structure

3-Methylsydnone

2-trimethylsilylphenyl triflate Structure

2-trimethylsily...

~78%

2-Methylindazole Structure

2-Methylindazole

4-Chloroaniline Structure

4-Chloroaniline

~%

Acetic acid,2-[(4-chlorophenyl)nitrosoamino]- Structure

Acetic acid,2-[...

ethyl 2-[(4-chlorophenyl)amino]acetate Structure

ethyl 2-[(4-chl...

~%

Acetic acid,2-[(4-chlorophenyl)nitrosoamino]- Structure

Acetic acid,2-[...

Benzo[d][1,3]dioxol-5-amine Structure

Benzo[d][1,3]di...

~%

3-benzo[1,3]dioxol-5-yl-1-oxa-2-aza-3-azoniacyclopent-3-en-5-one Structure

3-benzo[1,3]dio...

N-(3,4-methylendioxyphenyl)glycine ethyl ester Structure

N-(3,4-methylen...

~%

3-benzo[1,3]dioxol-5-yl-1-oxa-2-aza-3-azoniacyclopent-3-en-5-one Structure

3-benzo[1,3]dio...

Ethyl [(4-methylphenyl)amino]acetate Structure

Ethyl [(4-methy...

~%

2-[(4-methylphenyl)-nitroso-amino]acetic acid Structure

2-[(4-methylphe...

1-Fluoro-4-nitrobenzene Structure

1-Fluoro-4-nitr...

~%

Sydnone, 3- (p-nitrophenyl)- Structure

Sydnone, 3- (p-...

p-Toluidine Structure

~%

2-[(4-methylphenyl)-nitroso-amino]acetic acid Structure

2-[(4-methylphe...

p-Toluidine Structure

~%

Glycine,N-(4-methylphenyl)- Structure

Glycine,N-(4-me...

4-Bromoaniline Structure

~%

1,2,3-Oxadiazolium,3-(4-bromophenyl)-5-hydroxy-, inner salt Structure

1,2,3-Oxadiazol...

N-Phenylglycine Structure

N-Phenylglycine

~%

N/A Structure

5-METHOXY-2-PHENYL-2H-INDAZOLE Structure

5-METHOXY-2-PHE...

N-Phenyl-N-nitrosoglycine Structure

N-Phenyl-N-nitr...

~%

N/A Structure

5-METHOXY-2-PHENYL-2H-INDAZOLE Structure

5-METHOXY-2-PHE...

ethyl 2-[(4-chlorophenyl)amino]acetate Structure

ethyl 2-[(4-chl...

~98%

Glycine,N-(4-chlorophenyl)- Structure

Glycine,N-(4-ch...

4-Chloroaniline Structure

4-Chloroaniline

~%

Glycine,N-(4-chlorophenyl)- Structure

Glycine,N-(4-ch...

ethyl 2-[(4-chlorophenyl)amino]acetate Structure

ethyl 2-[(4-chl...

~%

3-(p-Chlorophenyl)sydnone Structure

3-(p-Chlorophen...

p-Anisidine Structure

~%

3-(4-methoxyphenyl)-1-oxa-2-aza-3-azoniacyclopent-3-en-5-one Structure

3-(4-methoxyphe...

ethyl 2-[(4-methoxyphenyl)amino]acetate Structure

ethyl 2-[(4-met...

~%

3-(4-methoxyphenyl)-1-oxa-2-aza-3-azoniacyclopent-3-en-5-one Structure

3-(4-methoxyphe...

2-trimethylsilylphenyl triflate Structure

2-trimethylsily...

1,2,3-Oxadiazolium,2,5-dihydro-5-oxo-3-phenyl-,innersalt(9CI) Structure

1,2,3-Oxadiazol...

~10%

2-phenylindazole Structure

2-phenylindazole

N-Phenylglycine Structure

N-Phenylglycine

~%

2-phenylindazole Structure

2-phenylindazole

N-Phenyl-N-nitrosoglycine Structure

N-Phenyl-N-nitr...

~%

2-phenylindazole Structure

2-phenylindazole

… Reaction of N-Aryl Sydnones with 2-Nitromethylenethiazolid...

[Azarifar, Davood; Bosra, Hassan Ghasemnejad; Zolfigol, Mohammad-Ali; Tajbaksh, Mahmood Heterocycles, 2006 , vol. 68, # 1 p. 175 - 181]