Indoles => aldehydes

Hopkins and Cole had obtained by the oxidation of tryptophane with ferric chloride a body of the composition of C9H7NO this body has been shown by Ellinger to be /8-indole-aldehyde, firstly by oxidising it to /8-indole-carboxylic acid,... 

The mitosene skeleton was readily formed by Wittig olefination of the indole-aldehyde 48 followed by RCM <02TL4765> (Scheme 27). 

The most puzzling of the Rauwoljia alkaloids is rauwolfinine, mp 235°-236°, [a]D — 35° (EtOH), which was first reported in 1954 (54) from a variety (Cochin) of R. serpentina and has been the subject of three additional papers (55) culminating in an analysis of its NMR-spectrum (56). Rauwolfinine was said to be an indoline alkaloid with one C methyl, and upon zinc dust or selenium dehydrogenation gave iV-methylharman. Rauwolfinine with 4 N sulfuric acid (55) was supposed to have afforded an indole [specifically, an indole aldehyde characterized as its 2,4-dinitro-... 

French group condensed indole aldehyde 198 with the appropriate metalated aromatic to give, after spontaneous oxidation of semiquinone 199, the desired quinone 200. Conventional amination yielded the target compounds (e.g., 201). Many such derivatives were prepared by Bisagni and co-workers (96), including the disubstituted compounds 202 and 203. 

This process involves a straightforward directed ortho metallation (chapter 7) of the pyridine amide 206 and capture by the indole aldehyde 208. Without work-up, the product 209 is lithiated again and the ellipticine quinone 210 is formed in good yield.26... 

Allylic alcohols can react with Mn02 under certain conditions to give the conjugated acid or ester (in alcoholic solvents). When indole aldehyde (104) was treated with Mn02 in the presence of NaCN and methanol, for example, a 75% yield of methyl ester (105) was ohtained.i63... 

Nitrones generated from indole aldehydes readily undergo 1,3-dipolar cycloadditions to adjacent allyl double bonds. Pyrrolo[l,2-a]indoles are formed from l-allylindole-2-carbaldehydes (Scheme 137) <89TL1421,93AJC603>, whilst pyrrolo[3,2,1-i/lquinolines are obtained from l-allylindole-7-car-baldehydes (Scheme 138) <93AJC843>. 

Ch. 8 Hydroxyindoles, Indole Alcohols, and Indolethiols Ch. 9 Indole Aldehydes and Ketones... 

In 2013, Sun and co-workers demonstrated an elegant catalytic asymmetric multicomponent reaction of indoles, aldehydes 35, and amines catalyzed by 2.5 mol% of CPA (l )-32b. The reaction has been designed for the... 

Zeokarb-225 is a heterogenous, recyclable, eco-benign catalyst for the liquid-phase electrophilic substitution reactions of indoles with aldehydes or indole aldehydes to afford the corresponding bis(indolyl)methanes or tris(indolyl)methanes in good yields (Scheme 2.4). The catalyst is also effective for the synthesis of new diindolyl-carbazolylmethanes in good yields (Magesh et al. 2004). 

Write out the synthesis of tryptophan from the appropriate indole aldehyde using this method. 

In addition to the reagents for detection which are quoted in Table 88, many others have been mentioned in the literature [89, 90, 104] for urine metabolites [78] for serotonine metabolites [14] for hydroxyindoles and -tryptophans [35] with comprehensive data for hydroxyskatoles [19] for the methyl esters of indole-carboxylic acids [i2, 23, 63] for glucobrassicin. 2,4-Dinitrophenylhydrazine (Rgt. No. 82) is suitable for the often feebly reactive indole-aldehydes. 

A few Lewis acids have been shown to catalyze the Yonemitsu-type reactions of indoles, aldehydes, and several CH acids (Scheme 13.79). Dimethyhnalonate 358 was successfully reacted with indole 327 and several aldehydes 357 under solvent-free ultrasound irradiation conditions to provide the desired products 359 in moderate yields [135]. Ytterbium triflate was used as the Lewis-acidic catalyst in this case. A copper-salen complex was utilized in water at elevated temperature to facilitate the Yonemitsu-type reaction of indoles 360, aldehydes 361, and malonodinitrile 21 [136]. In close similarity copper(II) acetate was used in polyethylene glycol at elevated temperatures to provide Yonemitsu-type products 366 in moderate to high yields (48-98%) [137]. 

Methoxy.indol-aldehyd-(3) 21II424. 7.Methoxy.indol.aldehyd-(3) 21II424. 

Verbindung C 5H]7C1N202( ) aua Indol aldehyd-anilin 21 II262. 

The synthesis of tiyptophan in 17% over-all yield from 3-indole-aldehyde was described by Majima and Kotake (549) in 1922. The method is indicated by the following equations. 3-Indolealdehyde - -hydantoin - - sodium acetate -f- acetic anhydride ) -indolalhydantoin ... 

Keywords Indoles, aldehydes, secondary amines, L-Proline, solvent-free, room temperature, one-pot multicomponent reaction, Mannich-type reaction, 3-amino alkylated indoles... 

Various intermediate products derived from tryptophane have been reported as occasional urinary constituents. These include indole aldehyde, indole acetic acid, scatoxyl, and indole carboxylic acid. Indole and scatole, themselves, are improbable urinary constituents. 

Indol-3yl-acetic acid (lAA) also in dolylacetonitrile, indole aldehyde and other indole derivatives, some of which have still to he chemically characterised. 

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