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Michael addition propargylic ester

Methyl perfluoromethacrylate reacts with allyl and propargyl alcohols to give the Michael addition products 19 and 20, respectively these eliminate hydrogen fluoride in the presence of the boron trifluoride-triethylamine complex and rearrange to acyl fluorides 21 and 22. Hydrolysis of the acyl fluorides with base results in decarboxylation to give the 2-(trifluoromethyl) esters 23 and 24.11... [Pg.202]

A related one-pot three component coupling reaction leading to allyli-dene tetrahydrofuran derivatives 80 and which combines a conjugate addition of a propargyl alcohol with an activated olefin and an in situ palladium-catalyzed carbopalladation-cyclization in the presence of a large excess of allyl chloride has been recently developed by Lu and Iiu (Scheme 31) [77]. The cyclization process is here initiated by addition of a catalytic amount of Pd(OAc)2 and in marked contrast with the above-discussed reactions, a catalytic cycle involving divalent palladium proceeds in the reaction. In this process, the ester enolate formed in the Michael addition undergoes... [Pg.135]

A mercury-free route to allyl vinyl ethers that relies on the Michael addition of allyl alcohols to unsubstituted alkenyl sulfoxides, followed by thermal loss of sulfenic acid and concurrent Claisen rearrangement has been described [145]. This methodology has been applied to the synthesis of isocar-bacyclin [146]. Posner reported an acid-catalyzed protocol that produces conjugated dienoate esters from allylic alcohols and a sulfinyl orthoester [147]. Additionally, the use of propargyl alcoholates and a chloro alkenyl sulfox-... [Pg.121]

A gold-catalysed 3 + 2-cycloaddition-hydrolytic Michael addition-retro-aldol reaction of propargyl esters tethered to cyclohexadienones gives tetrahydrofuranones, diox-atricycloundecenones, and furofurans (Scheme 112). The product cyclohexenones or cyclohexanones with a y-quaternary centre result from multiatom transpositions... [Pg.517]


See other pages where Michael addition propargylic ester is mentioned: [Pg.162]    [Pg.46]    [Pg.291]    [Pg.294]    [Pg.182]    [Pg.352]    [Pg.690]    [Pg.105]    [Pg.41]    [Pg.255]    [Pg.692]    [Pg.114]    [Pg.159]    [Pg.72]    [Pg.343]    [Pg.17]    [Pg.537]   
See also in sourсe #XX -- [ Pg.616 ]




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Additives esters

Esters Michael addition

Propargylic esters

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