2-lithio-5-methyl

Furan, 2-(p-hydroxyphenyI)-2,5-dihydro-synthesis, 4, 677 Furan, 3-hydroxytriphenyl-tautomerism, aromaticity and, 4, 595 Furan, iodo-synthesis, 4, 712 Furan, 2-iodo-Grignard reagents, 4, 79 Furan, 5-iodo-2-nitro-synthesis, 4, 711 Furan, 2-isopropyl-cycloaddition reactions with ff, ,a, ff -tetrabromoacetone, 1, 418 Furan, 2-lithio-5-methyl-synthesis, 1, 419 Furan, 2-mercapto-tautomerism, 4, 38 Furan, 3-mercapto-tautomerism, 4, 38 Furan, methoxy-planarity, 4, 544 synthesis, 4, 664 Furan, 2-methoxy-synthesis, 4, 648 Furan, 3-methoxy-Diels-Alder reaction, 1, 416 synthesis, 4, 649... 

The use of 4,5-dihydro-2-lithio-5-methyl-l,3,5-dithiazine instead of 2-lithio-1,3-dithian gives better results in the chain extension of sugars, the former being more reactive and the products more readily desulphurized. ... 

The synthesis of the 1-methyl derivative of sempervirine was achieved by Woodward and McLamore who condensed 1-lithio-methyl-9-methyl-jS-carboline (386) with 2-isopropoxymethylenecyclo-hexanone (387) treatment of the reaction product with hydrochloric acid gave im -W-methylsempervirinium chloride (cf. 388). 

The first report2 describes the addition of lithio (+)-(/ )-methyl 4-tolyl sulfoxide (1) to benzyl-ideneaniline (2, R1 = R2 = C6I15) which proceeds with diastcrcoselcctivities of >97 3(NMRof the crude material) to give the /(-amino sulfoxide 3a in 70% yield. 

Fig. 2.5. Comparison of energy profile (AG) for pathways to E- and Z-product from the reaction of lithio methyl dimethylphosphonoacetate and acetaldehyde. One molecule of dimethyl ether is coordinated to the lithium ion. Reproduced from J. Org. Chem., 64, 6815 (1999), by permission of the American Chemical Society.

OXAZOLES Copper(I) oxide. Lithio-methyl isocyanidc. 

Phenyl phenylselenomethyl tellurium and lithium diisopropylamide in tetrahydrofuran at —78° produced phenylphenylseleno(lithio)methyl tellurium. This compound reacted with methyl iodide to give phenyl 1-phenylseleno-l-ethyl tellurium2. Butyl lithium cleaved... 

Methan Lithio-[methyl-(2-natriumo-xy-ethyl)]-amino- E19d, 1045 (SnR3 - Li)... 

Propen l,3-Dilithio-2-(lithio-methyl)-3-(N-inethyl-anilino)-E19d, 456 (H -> Li)... 

Diazoalkyl and Azidoalkyl Acids. - A convenient synthesis of dimethyl (diazomethyl)phosphonate involves the initial interaction of dimethyl (lithio-methyl)phosphonate and 2,2,2-trifluoroethyl trifluoroacetate, followed by further reaction with an arylsulfonyl azide. " The compounds (192) (R R = dialkyl or... 

The preparation of the l,2-disila-4-heterocyclopentanes occurs by reaction of l,2-bis(lithio-methyl)di silanes with dichloroelement compounds or by reaction of bis(lithiomethyl)element compounds with 1,2-dichlorodisilanes (Scheme 2). 

A quite different method converted the amino moiety of isoleucine to an hydroxyl group (see 6.204). Conversion to the azide, reduction to the amine and condensation of the ester with lithio methyl (2-trimethylsilyloxycarboxy) acetate gave 6.205. Sodium borohydride reduction gave 6.206, along with 9% of 5.207. Hydrolysis and re-protection of 6.206 gave N-Boc isostatine, 6.208. In this work, it was noted that amino acid 6.208 is a component of didemnin cyclodipeptide. 

Indol-2-ylcopper reagents can also be prepared from 2-lithioindoles and they have some potential for the preparation of 2-substituted indoles. 1-Methyl-indol-2-ylcopper can be prepared by reaction of 2-lithio-l-methylindole with CuBr[10]. It reacts with aryl iodides to give 2-aryl-1-methylindoles. Mixed cyanocuprate reagents can be prepared using CuCN[ll], The cyan-ocuprate from 1-methylindole reacts with allyl bromide to give 2-allyl-l-methylindole. 

Hthiated 4-substituted-2-methylthia2oles (171) at -78 C (Scheme 80). Crossover experiments at—78 and 25°C using thiazoles bearing different substituents (R = Me, Ph) proved that at low temperature the lithioderivatives (172 and 173) do not exchange H/Li and that the product ratios (175/176) observed are the result of independent metala-tion of the 2-methyl and the C-5 positions in a kinetically controlled process (444). At elevated temperatures the thermodynamic acidities prevail and the resonance stabilized benzyl-type anion (Scheme 81) becomes more abundant, so that in fine the kinetic lithio derivative is 173, whereas the thermodynamic derivative is 172. 

The transmetallation of lithio derivatives with either magnesium bromide or zinc chloride has been employed to increase further their range of synthetic application. While the reaction of l-methyl-2-pyrrolyllithium with iodobenzene in the presence of a palladium catalyst gives only a poor yield (29%) of coupled product, the yield can be dramatically improved (to 96%) by first converting the lithium compound into a magnesium or zinc derivative (Scheme 83) (81TL5319). 

Benzo[h]selenophene, 7-hydroxy-synthesis, 4, 969 Benzo[h]selenophene, 3-lithio-synthesis, 4, 955 Benzo[h]selenophene, 2-methyl-mass spectra, 4, 942 synthesis, 4, 961 Benzo[h]selenophene, 3-methyl-mass spectra, 4, 942 synthesis, 4, 956... 

Benzo[h]tellurophene, 2,3-dihydro-3-oxo-halogenation, 4, 948 Benzo[h]tellurophene, 3-halo-synthesis, 4, 116, 966 Benzo[b]tellutophene, 3-hydroxy-tautomerism, 4, 37, 945 Benzo[h]tellurophene, 3-lithio-reactions, 4, 956 Benzo[h]tellurophene, 2-methyl-synthesis, 4, 952... 

Furan, 2,5-di hydro-2,5-dimethoxy- C NMR, 4, 573 heat of hydrogenation, 4, 592 Furan, 2,5-dihydro-3,4-dimethylene- H NMR, 4, 577 Furan, 2,3-dihydro-3-hydroxy-synthesis, 4, 685 Furan, 2,3-dihydro-5-lithio- C NMR, 4, 572 Furan, 2,3-dihydro-3-methyl- H NMR, 4, 570... 

Imidazole, 1 -hydroxy-2,4,5-triphenyl-3-oxides reactions, S, 455 Imidazole, iodo-nitrodehalogenation, 5, 396-397 Imidazole, 1-iodo-reactions, S, 454 stability, S, 110 Imidazole, 2-iodo-synthesis, S, 401 Imidazole, N-iodo-, S, 393 reactions, 5, 454 Imidazole, 4-iodo-5-methyl-iodination, 5, 400 Imidazole, 2-isopropyl-4-nitro-N-nitration, 5, 351 Imidazole, 2-lithio-reactions, S, 106, 448 Imidazole, 2-mercapto-l-methyl-as antithyroid drug, 1, 171 mass spectra, 5, 358 Imidazole, 1-methoxymethyl-acylation, S, 402 Imidazole, 5-methoxy-l-methyl-reactions... 

Indole, 3-hydroxymethyl-2-phenyl-stability, 4, 272 Indole, I-hydroxy-2-phenyl-synthesis, 4, 363 Indole, 2-iodo-synthesis, 4, 216 Indole, 3-iodo-reaetions, 4, 307 synthesis, 4, 216 Indole, 2-iodo-l-methyl-reaetions, 4, 307 Indole, 2-lithio-synthesis, 4, 308 Indole, 3-lithio-synthesis, 4, 308 Indole, 2-mereapto-tautomerism, 4, 38, 199 Indole, 3-mercapto-tautomerism, 4, 38, 199 Indole, 3-methoxy-synthesis, 4, 367 Indole, 5-methoxy-oxidation, 4, 248 Indole, 7-methoxy-2,3-dimethyl-aeetylation, 4, 219 benzoylation, 4, 219 Indole, 5-methoxy-l-methyl-reduetion, 4, 256 Indole, 5-methoxy-l-methyl-3-(2-dimethylaminoethyl)-reaetions... 

Oxirane, 2-lithio-2-triphenylsilyl-, 7, 25 Oxirane, methyl-catalyst... 

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