193686-80-5Relevant academic research and scientific papers
A new synthesis of 2-nitroindoles
Jiang, Jun,Gribble, Gordon W
, p. 4115 - 4117 (2002)
The C-2 lithiation of N-Boc- and N-(phenylsulfonyl)indoles (4-7) followed by reaction with dinitrogen tetroxide at low temperature affords the corresponding 2-nitroindoles 10-13 in 63-78% yields. Deprotection of the N-Boc-2-nitroindoles (10, 11) with trifluoroacetic acid gives 2-nitroindole (3) and 3-methyl-2-nitroindole (14) in essentially quantitative yields.
Convenient synthesis of masked aminoindoles by indium mediated one-pot reductive acylation of 3- and 2-nitroindoles
Roy, Sujata,Gribble, Gordon W.
, p. 51 - 56 (2007/10/03)
Unstable 3- and 2-aminoindoles arc generated in situ by indium mediated reduction of 3- and 2-nitroindoles and capped as the stable amides (or carbamate) in moderate to high yields under mild conditions in a one-pot procedure.
A convenient synthesis of 2-nitroindoles
Roy, Sujata,Gribble, Gordon W.
, p. 1325 - 1328 (2007/10/03)
The reaction of 2-iodo- and 2-bromoindoles with silver nitrite in aqueous acetone affords the corresponding 2-nitroindoles in modest to good yields.
Regioselective 1,3-dipolar cycloaddition reactions of unsymmetrical munchnones (1,3-oxazolium-5-olates) with 2- and 3-nitroindoles. A new synthesis of pyrrolo[3,4-b]indoles
Gribble, Gordon W.,Pelkey, Erin T.,Simon, Wendy M.,Trujillo, Hernando A.
, p. 10133 - 10140 (2007/10/03)
The unsymmetrical mesoionic munchnones 13 (3-benzyl-2-methyl-4-phenyl-1,3-oxazolium-5-olate) and 14 (3-benzyl-4-methyl-2-phenyl-1,3-oxazolium-5-olate) react with the N-protected 2- and 3-nitroindoles 1 (ethyl 2-nitroindole-1-carboxylate), 6 (3-nitro-1-(phenylsulfonyl)indole), and 17 (ethyl 3-nitroindole-carboxylate) in refluxing THF to afford in good to excellent yields the pyrrolo[3,4-b]indoles 15 (2-benzyl-1-methyl-3-phenyl-4-carboethoxy-2,4-dihydropyrrolo[3,4-b]indole), 16 (2-benzyl-3-methyl-1-phenyl-4-carboethoxy-2,4-dihydropyrrolo[3,4-b]indole), 18 (2-benzylmethyl-3-phenyl-4-(phenylsulfonyl)-2,4-dihydropyrrolo[3,4-b]indole), and 19 (2-benzyl-3-methyl-1-phenyl-4-(phenylsulfonyl)-2,4-dihydropyrrolo[3,4-b]indol e). In several cases the regiochemistry, which is opposite to that predicted by FMO theory, is very high and leads essentially to a single pyrrolo[3,4-b]indole; e.g., 6+ 13→19 in 74% yield. (C) 2000 Elsevier Science Ltd.
Synthesis of 2-nitroindoles via the Sundberg indole synthesis
Pelkey, Erin T.,Gribble, Gordon W.
, p. 5603 - 5606 (2007/10/03)
A three-step sequence has been developed for converting o-nitrobenzaldehydes into 2-nitroindoles. The key step involves the thermolysis of 2-(o-azidophenyl)nitroethylene (10) in xylenes which gives 2-nitroindole (4) in 54% yield, akin to the classic Sundberg indole synthesis. This procedure has also been utilized to synthesize 5,6-dimethoxy-2-nitroindole (14).
