Quinoline 3- trimethylstannyl

Quinoline, 2,2,4-trimethyl-1,2-dihydro-antioxidant in polymers, 1, 395 Doebner-von Miller synthesis, 2, 468 Quinoline, trimethylstannyl-reactions, 2, 364 Quinoline, 4-vinyl-polymers, 1, 286... 

Halogen exchange with metallic derivatives provides a powerful means of introducing iodine into specific quinoline sites. It has proved possible to prepare 2-, 3-, and 4-iodoquinolines from the trimethylstannyl [82H(19)168] or lithium derivatives [86S670]. Protected 2-aminoquinoline, lithiated at C-3, was quenched with iodine to give a 90% yield of the 3-iodo derivative (86S670). 

Trimethylstannyl-pyridines and -quinolines have been used for the introduction of an acyl group into the nucleus. The reaction occurs most readily with the 2-isomers, e.g. Scheme 148 <82H(19)4l). 

Yamamoto and Yanagi [24] have prepared iodoazines through iodo-destannation of trimethylstannylazines. Trimethylstannyl sodium was prepared in situ from chlorotrimethyl-stannane and metallic sodium. Subsequent treatment of 2-chloroquinoline 25 with trimethylstannyl sodium gave 2-trimethylstannylquinoline 41. Likewise, 3- and 4-trimethyl-stannyl quinolines 42 and 44 were converted to 3- and 4-iodoquinolines 43 and 45 in 96 and 91% yield, respectively via iodo-destannation. In the same fashion, 2,4-bis (trimethylstannyl)quinoline was synthesized from 4-bromo-2-chloroquinoline using two equivalents of trimethylstannyl sodium in 65% yield. 

The S Ar reaction between 2-chloroquinoline 25 and trimethylstannyl sodium led to 2-trimethylstannylquinoline 41 as shown previously. Similarly, 3-trimethylstannyl quinoline 49 and 4-trimethylstannyl quinoline 51 were prepared from 3-chloroquinoline 48 and... 

Pyridines (and quinolines) bearing a trimethylstannyl (SnMes) substituent at the 2-, 3-, or 4-position undergo iododemetallation to give the corresponding iodo-derivatives upon treatment with iodine. The trimethylstannyl compounds are themselves prepared by the reaction of the corresponding chloro-or bromo-derivatives with trimethylstannylsodium. The selective 3-debro-mination of 3,5-dibromo-4-hydroxy-2-pyridone has been reported. The reaction of 3-chloro-4-cyanopyridine with methanolic sodium methoxide gives the imino-ether (24) whereas treatment with sodium methoxide in DMF... 

Nucleophilic addition of 1005 to an 7V-acyliminium ion, e.g., a Reissert salt, and oxidation of the resulting adduct affords a 2-(heteroaryl)oxazole 1019. Acylation of a nitrogen heterocycle 1016 with ethyl chloroformate generated the intermediate Reissert salts 1017 in situ (Scheme 1.272). Addition of 1005 to 1017 gave adducts 1018, which produced 1019 after oxidative deacylation with o-chloranil. Examples of 2-(heteroaryl)oxazoles prepared from thiazole, benzothia-zole, pyridine, quinoline, and isoquinoUne are shown in Table 1.77. Donodni and co-workers summarized their early work on preparation and reaction of 2-(trimethylstannyl)oxazoles and 2-(trimethylsilyl)oxazoles. 

In respect to the Suzuki and the Negishi couplings, quinoline stannanes provide an easy entry to highly substituted derivatives. As a highlighted example, 2-trimethylstannyl-5,8-dimethoxyquinoline reacts with appropriately substituted pyridyltriflate in the presence of palladium tetrakis-(triphenylphospine), lithium chloride, and copper bromide to produce 2-pyridylquinoline, an advance intermediate for the total syntheses of antitumor compounds streptonigrin and lavendamycin. ... 

Acetone cyanhydrin and aluminium chloride may be used in place of hydrogen cyanide in the Gattermann formylation of aromatic compounds. Yields and substrate reactivities are comparable to those observed with the Gattermann procedure. The trimethylstannyl groups in stannyl-pyridines and -quinolines may be replaced regiospecifically by acyl groups by reaction with acyl chlorides. When the tin substituent is not at the 2-position, palladium catalysis is necessary, but this also leads to a small amount of formation of a bipyridyl [equation (10)1. 

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