Catalyzed Claisen rearrangment

Chorismate Mutase catalyzed Claisen Rearrangement- 10 rate enhancement over non-enzymatic reaction... 

Al-Allyl-2(l//)-pyridones 41 are obtained by a palladium(II)-catalyzed Claisen rearrangement of 2-(allyloxy)pyridines 40 <96TL(37)2829>. 

Sattelkau and Eilbracht90 have exploited the Claisen rearrangement of allyl vinyl ethers in their synthesis of several spiro compounds. As shown below in equation 62, 7,9-dimethyl-l,4-dioxa-spiro[4,5]decan-8-one, 118, was converted to a ,/J-unsaturated ester 119 which was reduced to allyl alcohol 120906. Allyl vinyl ether 121 underwent a rhodium-catalyzed Claisen rearrangement to afford 7r,13r-dimethyl-l,4-dioxa-(8rC9)-dispiro[4.2.4.2]tetradecan-10-one (122) in 36% yield. 

The allyl aryl ether 183 is converted into the 2-methylbenzofuran in a one-pot procedure via sequential Pd-catalyzed Claisen rearrangement and oxidative cyclization mediated by stoichiometric quantities of 1,4-benzoqui-none (BQ) (Equation 119) <2005OL3355>. 

For example, Kitazume and Zulfiqar have investigated the scandium(III) trifluorometh-anesulfonate catalyzed Claisen rearrangement of several aromatic allyl ethers in a neutral trifluoromethanesulfonate ionic liquids [45]. The reaction initially gave the 2-allylphenol but this reacted further to give 2-methyl-2,3-dihydrobenzo[b]furan (Scheme 2). The yields in this reaction were highly dependant on the ionic liquid chosen, with [EDBU][OTf ] giving the best yields (e.g. 91% for R = 6-CH3). 

A Pd(0)-catalyzed Claisen rearrangement with a subsequent intramolecular Heck vinylation has been demonstrated by Watson and coworkers [84], Upon treatment with Pd(PPh3)4 the allyl vinyl ether undergoes a Pd(0)-catalyzed 1,3 oxygen to carbon allyl shift to afford an a-allyl ketone that... 

Lewis Acid-Catalyzed Claisen Rearrangements in the Preparation of Chiral Products... 

Cyclic 1,2-diketones, such as3-methylcyclopentane-l,2-dione, act as oxygen nucleophiles in palladium(0)-catalyzed reactions with a range of cyclic and acyclic allylic esters. The products of these reactions were subjected to a lanthanide-catalyzed Claisen rearrangement to access the C-alkylated products. 

Other leaving groups like the enantiomerically pure imidate85 (Table 8, entry 11) can also be used to give the substituted product with net retention of configuration. Without an external nucleophile, transition metal-catalyzed Claisen rearrangement occurs for allyl imidates. 

For the uncatalyzed and chorismate mutase catalyzed Claisen rearrangement of (Z)-9-methylchorismic acid see ref 271. For a Claisen-type rearrangement of an 0-(3,3-dimethylal-lyl)tyrosine derivative in the sirodesmin biosynthesis cf. ref 272. 

I.6.3.I.I.2.2. Catalyzed Claisen Rearrangements Organoaluminmn-Promoted Rearrangements Acyclic Substrates... 

The bis(2,6-diphenylphenoxy)inethylaluminum catalyzed Claisen rearrangement was used as the key step in the synthesis of (4 . 7Z)-trideca-4,7-dienyl acetate (3), a component of the sex pheromone of the potato tuberworm moth Phthorimaea operculella 13. 

Dimethylphenol (DMP) catalyzed Claisen rearrangements result exclusively in products with an -double-bond configuration (see also Section 1.6.3.1.1.4.2.3., p 3445 and note on p 3447), e.g. formation of 1 and 2344. 

Palladium-Catalyzed Claisen Rearrangement General Procedure135 ... 

Scheme 7.43 Acid-catalyzed Claisen rearrangement of poly(4-cyclohexenyloxy styrene).

Scheme 34 Two models of the metal-catalyzed Claisen rearrangement...

Jackson, D.Y. Liang. M.N. Bartlett, P.A. Schultz, P.G. Activation parameters and stereochemistry of an antibody-catalyzed Claisen rearrangement. Angew. Chem., Int. Ed. 

For the design of organometallic catalytic reactions, one can apply stereoelectronic effects that are specific to the metal centers, such as the trans-effect. An interesting manifestation of this effect in the Rh-catalyzed Claisen rearrangement of propargyl vinyl ethers (Figure 11.13) was found in the computational analysis of this process. ... 

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