5- Methyl isatin

Methyl isatin, 5, 74 o-Methyl Mannoside, 7, 64, 66 Methyl jtc-Nitrobenzoate, 3, 71, 73 Methyl c-nitrobenzoate, 3, 72 Methyl oxalate,, 60... 

Methylene iodide, I, 57-59 /3-Methyl esculetin, IV, 45-46 (//-Methyl ethyl acetic acid, V, 75-77 Methyl formate, III, 67 Methyl hexyl carbinol, I, 61-66 Methyl iodide, I, 57, 59 5-Methyl isatin, V, 74 Methyl o-nitrobenzoate, III, 72 Methyl m-nitrobenzoate, III, 71-72, 73-Methyl oxalate, V, 60 Methyl Red, II, 47-51... 

A number of studies of the ultraviolet absorption spectra of isatins have appeared.34,232-235 The absorption curves of isatin and A -methyl-isatin are practically identical.233... 

Generally, however, lithium aluminium hydride reduction is used to convert isatins to indoles. Thus, 4,5,6-trimethoxyisatin,251 5-bromo-isatin,252 5-chloro-6-methoxy-l-methylisatin,253 1-ethyl- and 1-methyl-isatin,254 and 4,6-dimethoxyisatin94 all gave the corresponding indoles. 

Treatment of isatin-3-thiosemicarbazone333,394,395 and N-methyl-isatin-3-thiosemicarbazone333,395 with 1AT alkali gave 108 which on treatment with alkali and iodine gave 109,395 and with alkali and methyl iodide gave HO.333,396 Ring opening also took place in the preparation of 108 (R = Me).333 Treatment of 108 (R = Me) with... 

The Menshutkin acid chloride was used by the author of [19] for the cyclization of isatin derivatives, and l-[(perhydro-2-alkoxy-l,3,6,2-dioxaazophosphocin-6-yl)methyl]isatins (53) were obtained ... 

This is prepared in a similar way to the preceding compound, the isatin being replaced by methyl-isatin. Crystallised from ethylene glycol, it is a fine, white powder, unmdted below 250° C. Its earbethonsy- and carbom hoaiy-derwaiives do not melt below 275° C. Its arseno-compound, p p -di-4i-carboiBy-Q-methylgpunoUne-2 -arsenobenzene, is a radish-brown product, unmelted bdow 260° C. 

Later, Ye and coworkers developed a highly enantioselective synthesis of spiro-cyclic oxindole-p-lactones by a [2-1-2] cycloaddition reaction between isatins and ketenes catalyzed by A-heterocyclic carbenes (NHCs) [57]. TheA-methyl isatin 54c reacted with various aromatic ketenes 100 in the presence of an NHC precursor XXVI at -40 °C to afford the corresponding spirocyclic oxindole-p-lactones 101 in good yields and enantioselectivities, as shown in Scheme 10.36. 

Methisa2one [1910-68-5] C qH qN OS (l-methyl-3-thiosemicarba2one of 2-oxoindole, (7), one of the more active in the isatin-3-thiosernicarba2one [487-16-1] series, has been used in the treatment and prevention of smallpox and vaccinia infections that develop as complications of smallpox vaccination... 

Isatin (190) is a compound with interesting chemistry. It can be iV-acetylated with acetic anhydride, iV-methylated via its sodium or potassium salt and O-methylated via its silver salt. Oxidation of isatins with hydrogen peroxide in methanolic sodium methoxide yields methyl anthranilates (81AG(E)882>. In moist air, O-methylisatin (191) forms methylisatoid (192). Isatin forms normal carbonyl derivatives (193) with ketonic reagents such as hydroxylamine and phenylhydrazine and the reactive 3-carbonyl group also undergoes aldol condensation with active methylene compounds. Isatin forms a complex derivative, isamic acid (194), with ammonia (76JCS(P1)2004). 

Buu-Hoi has shown that n-alkyl methyl ketones excluding ethyl methyl ketone, yield primarily 2-monosubstituted cinchoninic acids. It has been demonstrated that the products of the condensation of isatin with aryloxyketones are the corresponding 3-aryloxy-4-quinoline carboxylic acids rather than the isomeric 2-aryloxymethylcinchoninic acids.In the case of simple a-alkoxyketones such as 1-alkoxyethyl methylketones, the preferred products are the 2-alkoxyalkylcinchoninic... 

Condensation of Isatin 3 with Ethyl Methyl Ketone 39/... 

A mixture of 60 g (0.408 mol) of isatin, 200 mL of 34% potassium hydroxide in diluted alcohol solution, 88 g (1.22 mol) of ethyl methyl ketone and 375 mL of water were stirred and heated under reflux for 72 hours. About 125 mL of liquid was removed by distillation the residue was made slightly acidic and filtered. The filtrate was made strongly acidic to precipitate the reaction product, which was collected by filtration, washed, dried, weighed 70 g (85% yield). 

Thianaphtheneqiiinone - (109) and diazomethane give a different reaction from that found with isatin, A -methylisatin and coumarandione. In as far as crystalline products could be isolated, the ring expansion occurs here between the sulfur and the carbonyl group in the 2-position. Depending on the solvent, there are formed 3-hydroxy-thiochromone (110), its 0-methyl derivative (111), or (presumably by attack on the 3-keto group of the tautomeric 3,4-diketo form of 110), 3,3 -epoxy-3-methylthiochromone (108). 

Bei der Reduktion von 2-Oxo-2,3-dihydro-indolen liegen die Ausbeuten iiber 80% d.Th. Das 3-Methyl-Derivat ergibt z. B. quantitativ 3-Methyl-indol (Skatol) Aus den Isatinen erhalt man die entsprechenden Indole in 45-80%iger Ausbeute. Isatin selbst liefert 72% d.Th. Indol. Zur Herstellung von 3,3-Bi-indolen aus den entsprechenden Lactamen s. Lit.4. 

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