Indole, 1,2-dimethyl-, reaction

Jap-KIingermarm reactions, 4, 301 oxidation, 4, 299 reactions, 4, 299 synthesis, 4, 362 tautomerism, 4, 38, 200 Indole, 5-amino-synthesis, 4, 341 Indole, C-amino-oxidation, 4, 299 tautomerism, 4, 298 Indole, 3-(2-aminobutyl)-as antidepressant, 4, 371 Indole, (2-aminoethyl)-synthesis, 4, 278 Indole, 3-(2-aminoethyl)-synthesis, 4, 337 Indole, aminomethyl-reactions, 4, 71 Indole, 4-aminomethyl-synthesis, 4, 150 Indole, (aminovinyl)-synthesis, 4, 286 Indole, 1-aroyl-oxidation, 4, 57 oxidative dimerization catalysis by Pd(II) salts, 4, 252 Indole, 1-aroyloxy-rearrangement, 4, 244 Indole, 2-aryl-nitration, 4, 211 nitrosation, 4, 210 synthesis, 4, 324 Indole, 3-(arylazo)-rearrangement, 4, 301 Indole, 3-(arylthio)-synthesis, 4, 368 Indole, 3-azophenyl-nitration, 4, 49 Indole, 1-benzenesulfonyl-by lithiation, 4, 238 Indole, 1-benzoyl photosensitized reactions with methyl acrylate, 4, 268 Indole, 3-benzoyl-l,2-dimethyl-reactions... 

Vilsmeier-Haack formylation, 4, 222 Indole, dimethyl- C NMR, 4, 172 Indole, 1,2-dimethyl-bis-allylation, 4, 357 Indole, 1,3-dimethyl-nitration, 4, 211 reactions... 

Reaction with indoles,5 Reaction with N,N-dimethyl(methylene)ammonium chloride is superior to reaction under conventional Mannich conditions for functionalization of various indoles. 

Indole, 3-(dialkylaminomethyl-) alkylation, 4, 275 Indole, 2,3-dibromo-synthesis, 4, 215 Indole, 2,6-dibromo-3-methyl-synthesis, 4, 215 Indole, 1,3-dichloro-synthesis, 4, 214 Indole, dihydrodehydrogenation, 4, 283, 311 in non-silver photography, 1, 383 Indole, 2,3-dihydro-synthesis, 4, 327, 352 Indole, 2,3-dihydroxy-tautomerism, 4, 37, 199 Indole, 4,6-dimethoxy-Vilsmeier-Haack formylation, 4, 222 Indole, dimethyl-l3C NMR, 4, 172 Indole, 1,2-dimethyl-bis-allylation, 4, 357 Indole, 1,3-dimethyl-nitration, 4, 211 reactions... 

Some final examples of the Makosza indole synthesis are tabulated in Table 2. Volovenko and colleague report a simple synthesis of 3-substituted-2-amino-5-nitroindoles (entry 1), which were transformed into pyrimido[l,2-fl] indoles upon reaction with p-dicarbonyl compounds [26]. A conventional VNS method was used by Lerman and colleagues to craft 6- and 7-hydroxyindoles via sacrificial chlorine atoms that serve to increase the electrophilicity of the benzene ring toward cyanomethylation. Subsequent transfer hydrogenation (Pd/C/HCO NH ) gives the respective hydroxyindoles (entries 2, 3) [27], The preparation of 3,6-dimethyl-5-methoxyindole by Skibo and coworkers (entry 4) was the starting point in a synthesis... 

Highly nucleophilic aromatic compounds are capable of arylating acyl-pyridinium salts. The first example of this striking reaction was described by Koenigs and Ruppelt s ho observed the formation of 4-(/>-dimethyl-aminophenyl) pyridine from pyridine, benzoyl chloride and dimethyl-aniline in the presence of copper. Benzaldehyde is also formed s, 736 and the copper is not necessaryThe dihydropyridine (105) is probably an intermediate. Other examples of the reaction are known s, 493 but attempts to isolate the intermediates have failed , though that from dimethyl-m-toluidine may have been obtained. In contrast, the dihydropyridines (106) were isolated when indole was the nucleophile. Skatole reacted similarly, at the 2-position of the indole nucleus, giving the fully aromatic 3-methyl-2-(4 -pyridyl)indole. These reactions failed with 2- and 4-picoline . Similar reactions occur between acylpyridinium salts and pyrroles (p. 71). 

Phenylindole reacts with dimethyl sulphoxide to give the 3-methylthio-homologue. Bis(2- and 3-indolyl) sulphides are accessible from the indoles by reaction with SCl2. ... 

A AlI lation. 1-Substitution is favored when the indole ring is deprotonated and the reaction medium promotes the nucleophilicity of the resulting indole anion. Conditions which typically result in A/-alkylation are generation of the sodium salt by sodium amide in Hquid ammonia, use of sodium hydride or a similar strong base in /V, /V- dim ethyl form am i de or dimethyl sulfoxide, or the use of phase-transfer conditions. 

Vinyl chloride reacts with sulfides, thiols, alcohols, and oximes in basic media. Reaction with hydrated sodium sulfide [1313-82-2] in a mixture of dimethyl sulfoxide [67-68-5] (DMSO) and potassium hydroxide [1310-58-3], KOH, yields divinyl sulfide [627-51-0] and sulfur-containing heterocycles (27). Various vinyl sulfides can be obtained by reacting vinyl chloride with thiols in the presence of base (28). Vinyl ethers are produced in similar fashion, from the reaction of vinyl chloride with alcohols in the presence of a strong base (29,30). A variety of pyrroles and indoles have also been prepared by reacting vinyl chloride with different ketoximes or oximes in a mixture of DMSO and KOH (31). 

Reaction of indole with excess of methyl iodide at 110°C gives a tetramethyl derivative (66). The intermediate 2,3-dimethylindole (65) is thought to arise by rearrangement of the 3,3-dimethyl-3Ff-indolium cation (64). 

Aminomethylindoles are particularly important synthetic intermediates. 3-Dimethyl-aminomethylindole (gramine) (153) and especially its quaternary salts readily undergo displacement reactions with nucleophiles (Scheme 60). Indole-2,3-quinodimethanes, generated from 2-methylgramine as shown in Scheme 61, undergo intermolecular cycloaddition reactions with dienophiles to yield carbazole derivatives (82T2745). 

In order to exploit the reactions of the C-lithio derivatives of iV-unsubstituted pyrroles and indoles, protecting groups such as t-butoxycarbonyl, benzenesulfonyl and dimethyl-amino have been used 81JOC157). This is illustrated by the scheme for preparing C-acylated pyrroles (211) (8UOC3760). 

An indole protected by a Mannich reaction with formaldehyde and dimethyl-amine is stable to lithiation. The protective group is removed with NaBH4 (EtOH, THE, reflux). The related piperidine analogue has been used similarly for the protection of a triazole. ... 

Indole on standing with dimethyl acetylenedicarboxylate for 74 days gave a 63% yield of the carbazole (55) along with 7-8% of each of two 1 3 molar adducts and about 2% of a 2 1 molar adduct for which no structures were suggested. It was proposed that the fumarate (56) was an intermediate, as it gave the carbazole (55) with the ester. However, as the yield in this last reaction, 26%, is much less than that obtained in the direct addition, it is very unlikely that (56) is, in fact, an intermediate, and an alternative reaction scheme as suggested here may be applicable. 

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