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Gold-catalyzed rearrangement

Representative procedure for the gold-catalyzed rearrangement/Diels-Alder reaction of propargyl pivatales. 4-Formyl-4,6-dimethyl-3-propylcyclohex-I-enyl pivalat ... [Pg.518]

Representative procedure for the gold-catalyzed rearrangement of aromatic propargyl acetates to indenes. 5-Butyl-5H-indeno[5,6-d][l,3]dioxol-5-yl acetate... [Pg.521]

The gold-catalyzed rearrangement of vinyl propargyl ethers such as 49 was reported by Toste and Sherry. The intermediate oxonium 50 was initially formed via a 6-endo-dig cyclization with the propargylic substituent occuping a pseudoaxial orientation to avoid A -strain with the alkenyl gold moiety. Allenic aldehyde 51 was then formed as 50 collapsed via a fragmentation pathway. ... [Pg.38]

An early example that shows the importance of the tuning of the steric properties of the ligands used was reported by Nolan and coworkers. They found that in the gold-catalyzed rearrangement of allyl acetates (see Scheme 9.20), only the use of the very sterically encumbering ICy and IPr ligands provided the... [Pg.280]

Scheme 9.20 Gold-catalyzed rearrangement of allyl acetates according to Nolan and coworkers [39]. Scheme 9.20 Gold-catalyzed rearrangement of allyl acetates according to Nolan and coworkers [39].
Scheme 16.17 Effect of an acyclic carbone ligand on selectivity in gold-catalyzed rearrangements. Scheme 16.17 Effect of an acyclic carbone ligand on selectivity in gold-catalyzed rearrangements.
Fiirstner, A., Hannen, P. (2006). Platinum- and gold-catalyzed rearrangement reactions of propargyl acetates total syntheses of (—)-alpha-cubebene, (—)-cubebol, sesquicarene and related terpenes. Chemistry - A European Journal, 12, 3006-3019. [Pg.151]

The Diels-Alder reaction outlined above is a typical example of the utilization of axially chiral allenes, accessible through 1,6-addition or other methods, to generate selectively new stereogenic centers. This transfer of chirality is also possible via in-termolecular Diels-Alder reactions of vinylallenes [57], aldol reactions of allenyl eno-lates [19f] and Ireland-Claisen rearrangements of silyl allenylketene acetals [58]. Furthermore, it has been utilized recently in the diastereoselective oxidation of titanium allenyl enolates (formed by deprotonation of /3-allenecarboxylates of type 65 and transmetalation with titanocene dichloride) with dimethyl dioxirane (DMDO) [25, 59] and in subsequent acid- or gold-catalyzed cycloisomerization reactions of a-hydroxyallenes into 2,5-dihydrofurans (cf. Chapter 15) [25, 59, 60],... [Pg.67]

Scheme 1. Gold-catalyzed skeletal rearrangement of a strained hydrocarbon. Scheme 1. Gold-catalyzed skeletal rearrangement of a strained hydrocarbon.
In the gold-catalyzed carbonylation of olefins according to Xu et al., gold(I) carbonyl complexes are considered as active catalysts this reaction proceeds already at room temperature in concentrated sulfuric acid at a CO pressure of 1 atm and leads after acid-catalyzed skeletal rearrangement to tertiary carboxylic acids such as 16,18, and 19 (Scheme 4) [11],... [Pg.50]

Representative procedure for the gold-catalyzed Claisen rearrangement of propargyl vinyl ethers. (R)-3-(2-Phenylvinylidene)heptan-l-of ... [Pg.467]

Representative procedure for the gold-catalyzed Meyer-Schuster-rearrangement of propargyl acetates. (E)-l-Phenyloct-2-en-4-on ... [Pg.517]

See other pages where Gold-catalyzed rearrangement is mentioned: [Pg.69]    [Pg.518]    [Pg.474]    [Pg.562]    [Pg.280]    [Pg.562]    [Pg.748]    [Pg.140]    [Pg.69]    [Pg.518]    [Pg.474]    [Pg.562]    [Pg.280]    [Pg.562]    [Pg.748]    [Pg.140]    [Pg.325]    [Pg.6580]    [Pg.6587]    [Pg.6591]    [Pg.121]    [Pg.6579]    [Pg.6586]    [Pg.6590]    [Pg.265]    [Pg.13]    [Pg.78]    [Pg.439]    [Pg.449]    [Pg.461]    [Pg.462]    [Pg.467]    [Pg.516]    [Pg.519]    [Pg.640]    [Pg.526]    [Pg.653]    [Pg.882]    [Pg.458]   
See also in sourсe #XX -- [ Pg.162 ]



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Gold-catalyzed

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