Simple synthesis of 7-formylindole was written by Uchil, Vinod;Gund, Machhindra;Satyam, Apparao. And the article was included in Synthetic Communications in 2006.Quality Control of (3-Methyl-2-nitrophenyl)methanol This article mentions the following:
A simple route to 7-formylindole is described in which appropriately functionalized o-nitrotoluenes are converted to 7-hydroxymethylindole (I) using the Batcho-Leimgruber process. Condensation of 3-methyl-2-nitrobenzyl alc. with N,N-dimethylformamide di-Me acetal yields the enamine, which upon catalytic hydrogenation affords I in 22% yield. When the hydroxyl function in functionalized o-nitrotoluenes is protected with pivaloyl or tetrahydropyranyl group, the yields of I are increased to 39% and 48%, resp. Finally, I is oxidized with pyridinium chlorochromate (PCC) to afford 7-formylindole in 86% yield. In the experiment, the researchers used many compounds, for example, (3-Methyl-2-nitrophenyl)methanol (cas: 80866-76-8Quality Control of (3-Methyl-2-nitrophenyl)methanol).
(3-Methyl-2-nitrophenyl)methanol (cas: 80866-76-8) belongs to alcohols. Similar to water, an alcohol can be pictured as having an sp3 hybridized tetrahedral oxygen atom with nonbonding pairs of electrons occupying two of the four sp3 hybrid orbitals. Grignard and organolithium reagents are powerful tools for organic synthesis, and the most common products of their reactions are alcohols.Quality Control of (3-Methyl-2-nitrophenyl)methanol
Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts