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Allyl-methyl-phenyl

Complexes 79 show several types of chemical reactions (87CCR229). Nucleophilic addition may proceed at the C2 and S atoms. In excess potassium cyanide, 79 (R = R = R" = R = H) forms mainly the allyl sulfide complex 82 (R = H, Nu = CN) (84JA2901). The reaction of sodium methylate, phenyl-, and 2-thienyllithium with 79 (R = R = r" = R = H) follows the same route. The fragment consisting of three coplanar carbon atoms is described as the allyl system over which the Tr-electron density is delocalized. The sulfur atom may participate in delocalization to some extent. Complex 82 (R = H, Nu = CN) may be proto-nated by hydrochloric acid to yield the product where the 2-cyanothiophene has been converted into 2,3-dihydro-2-cyanothiophene. The initial thiophene complex 79 (R = R = r" = R = H) reacts reversibly with tri-n-butylphosphine followed by the formation of 82 [R = H, Nu = P(n-Bu)3]. Less basic phosphines, such as methyldiphenylphosphine, add with much greater difficulty. The reaction of 79 (r2 = r3 = r4 = r5 = h) with the hydride anion [BH4, HFe(CO)4, HW(CO)J] followed by the formation of 82 (R = Nu, H) has also been studied in detail. When the hydride anion originates from HFe(CO)4, the process is complicated by the formation of side products 83 and 84. The 2-methylthiophene complex 79... [Pg.14]

The oxidative dimerization of the anion of methyl phenyl sulfone (from a Grignard reagent) in ethereal solution in the presence of cupric chloride in 5% yield has been reported47. Despite the reported48 poor stability of the a-sulfonyl C-centered radicals, Julia and coworkers49 provoked the dimerization (in 13 to 56% yields) of the lithiated carbanion of alkyl phenyl sulfones using cupric salts as oxidants. The best results are obtained with cupric triflates in THF-isobutyronitrile medium (56% yield for R = H). For allyl phenyl sulfones the coupling in the 3-3 mode is predominant. [Pg.1057]

Allyl-(2-methyl-phenyl)-ather AllyI-(2-chlor-phcnyl)-ather Allyl-naphthyl-( l)-ather Benzyl-naphthyl-(2)-ather... [Pg.414]

The formation of ethers such as 1806 by EtsSiH 84b can also be catalyzed by trityl perchlorate to convert, e.g., benzaldehyde in 84% yield into dibenzyl ether 1817 [48]. The combination of methyl phenethyl ketone 1813 with O-silylated 3-phenyl-n-pro-panol 1818, in the presence of trityl perchlorate, leads to the mixed ether 1819 in 68% yield [48] (Scheme 12.15). Instead of trityl perchlorate, the combination of trityl chloride with MesSiH 84a or EtsSiH 84b and sodium tetrakis[3,5-bis-(trifluoro-methyl)phenyl]borane as catalyst reduces carbonyl groups to ethers or olefins [49]. Employing TMSOTf 20 as catalyst gives very high yields of ethers. Thus benzaldehyde reacts with O-silylated allyl alcohol or O-silylated cyclohexanol to give the... [Pg.269]

In the alkaline hydrolysis of (R)-(+)-methyl(phenyl)(a-naphthyl)allylphos-phonium salts, the naphthyl group is cleaved with predominant retention of configuration at phosphorus, whereas the allyl group is lost with predominant inversion.127... [Pg.22]

R = 2,6-(di-fert-butyl)-4-methyl-phenyl Scheme 9.3 Allylic substitution at a (Z)-allylic substrate. [Pg.213]

Allylic and benzylic alcohols were oxidized to aldehydes or ketones with BnPhsPHSOs in refluxing CHsCN. The yield increased in the presence of bismuth chloride in a catalytic amount. Selective oxidation of various alcohols under solvent free conditions was also reported Interestingly, benzyl alcohols were oxidized selectively to benzaldehydes in very high yield (95-100%) when reacted with BnPhsPHSOs (1.2 eq.) and AICI3 (1 eq.) in the presence of an equimolar amount of 2-phenethyl alcohol, diphenyl carbinol or methyl phenyl sulfide (equation 72). [Pg.1031]

Conversion into 6-methyl-2-(4-methylphenyl)hepta- 1,5-diene. 2- 4-methyl-phenyl)prop-2-enyl vinyl ether. A mixture of the foregoing allylic alcohol (2.5 g), ethyl vinyl ether (75 ml) and freshly crystallised mercury(n) acetate (600 mg) is refluxed continuously for 12 hours on a water bath. The reaction mixture is chilled in ice and mixed with 10 per cent aqueous sodium carbonate solution (25 g) and stirred well for 30 minutes at 0 °C. The organic layer is... [Pg.797]

Palladium-mediated cydization based on the reactivity of o-alkynyl or alkenyl-phenyl isonitriles have been developed [105]. On the basis of their earlier studies on the three-component synthesis of allyl aryl cyanamides [106], Yamamoto and co-workers reported a palladium-catalyzed three-component coupling reaction of 2-alkynylisocyanobenzenes 122 with allyl methyl carbonate and trimethylsilylazide leading to N-cyanoindoles 125 [107]. One of the key steps of the proposed mechanism is the formation of 7i-allylpalladium carbodiimide 123 and its isomerization to rc-allylpalladium cyanamide complex 124 (Scheme 8.50). [Pg.253]

Goering, H. L. Tseng, C. C. Alkylation of allylic derivatives. 7. Stereochemistry of alkylation of the isomeric trans-a,y-methyl(phenyl)-allyl acetates with lithium dialkylcuprates and alkylcyanocuprates. J. Org. Chem. 1983, 48, 3986-3990. [Pg.134]

Acetoxy-3-allyl-6-methoxy- 1-phenyl-1, 8-naphthyridin-2(l//)-one 4-Acetoxy-3-allyl- 1-phenyl-1, 8-naphthyridin-2(l//)-one 4-Acetoxy-1 -benzyl-1,8-naphthyridin-2(l//)-one 1 -(3-Acetoxypropyl)-3-methyl-1, 8-naphthyridin-2(l//)-one... [Pg.368]

Allyl-methyl- E2, 262 (2-Amino-ethyl)-etbyl- E2, 263 (2-Amino-ethyl)-phenyl- E2, 263 -Anhydrid... [Pg.988]

N-Ethoxycarbonyl-4-allyl-4-methylpyrrolidin-2-yl)methyl phenyl tellurium yield 85%... [Pg.435]

Treatment of enantiomerically pure cyclic sulfonimidates 6 and 7 with allyllithium or allylmagnesium bromide gives optically active allylic sulfoximines 8 and 9 (R = allyl) as described in Section II.A.13 The reactions of /V-phenyl-S-(methyl-phenyl)sulfoximidoyl chloride 109 with allyltrimethylsilane or allyltributylstan-... [Pg.317]


See other pages where Allyl-methyl-phenyl is mentioned: [Pg.760]    [Pg.762]    [Pg.760]    [Pg.762]    [Pg.384]    [Pg.269]    [Pg.73]    [Pg.102]    [Pg.783]    [Pg.908]    [Pg.1421]    [Pg.73]    [Pg.102]    [Pg.783]    [Pg.84]    [Pg.105]    [Pg.55]    [Pg.487]    [Pg.884]    [Pg.199]    [Pg.487]    [Pg.884]    [Pg.1031]    [Pg.147]    [Pg.1102]    [Pg.131]    [Pg.75]    [Pg.368]    [Pg.1524]    [Pg.417]    [Pg.1009]    [Pg.1015]    [Pg.167]   
See also in sourсe #XX -- [ Pg.956 , Pg.1157 ]




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Allyl- -phenyl

Allyl-methyl

Allylic phenylation

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