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Transposition of alcohol and

Overman, L. E. Zipp, G. G. Allylic transposition of alcohol and amine functionality by thermal or Pd(II)-catalyzed rearrangements of allylic N-benzoylbenzimidates. J. Org. Chem. 1997, 62, 2288-2291. [Pg.259]

L. E. Overman, Thermal and mercuric ion catalyzed [3,3]-sigmatropic rearrangement of allylic trichloroacetimidates. 1,3-Transposition of alcohol and amine functions,. /. Am. Chem. Soc., 96 (1974) 597-599. [Pg.113]

Overman, L.E. and Zipp, G.G. 1997. AUyhc transposition of alcohol and amine functionality by thermal or palladium (ll)-catalyzed rearrangements of aUylic A-benzoylbenzimidates. Journal of Organic Chemistry, 62 2288-91. [Pg.211]

See also page 47, Section 93 and page 49, Section 9.4, for reduction of sulfur-containing derivatives of alcohols and phenols and page 229, Section 4, for reduction of allylic sulfonates and sulfones with double bond transposition. [Pg.53]

Besides oxidation reactions, MTO supported on AI2O3/ Si02, niobia, or zeolites also catalyzes the metathesis of functionalized alkenes, 1,2 transposition of allylic alcohols, addition of epoxides to ketones, alkoxylation of epoxides, dehydration and amination of alcohols, and... [Pg.4024]

Oxyselenenylation-oxidative deselenenylation (oxyselenenylation-selenoxide elimination) sequence provides the double-bond transpositioned allylic alcohols and ethers from alkenes. Oxyselenenylation of alkenes and its asymmetric... [Pg.245]

Sodium acyloxyborohydride has been found to effect the reduction of aliphatic and aromatic nitriles to the corresponding amines any chloro, nitro, or aromatic substituents remain unaffected under the reaction conditions. Full details have appeared of the [3,3]sigmatropic rearrangement of trichloroacetamidic esters of allylic alcohols, which provides a superior method for the 1,3-transposition of amino (and hydroxy) functions (Scheme 2). [Pg.184]

The transposition of the C=C bond and the alcohol functionality is highly stereospecific, erythro-g yciAo sulphonates giving cA-allylic alcohols and the f/ireo-isomer the trans-allylic alcohol. [Pg.131]

The first example of chemoenzymatic DKR of allylic alcohol derivatives was reported by Williams et al. [37]. Cyclic allylic acetates were deracemized by combining a lipase-catalyzed hydrolysis with a racemization via transposition of the acetate group, catalyzed by a Pd(II) complex. Despite a limitation of the process, i.e. long reaction times (19 days), this work was a significant step forward in the combination of enzymes and metals in one pot Some years later, Kim et al. considerably improved the DKR of allylic acetates using a Pd(0) complex for the racemization, which occurs through Tt-allyl(palladium) intermediates. The transesterification is catalyzed by a lipase (Candida antarctica lipase B, CALB) using isopropanol as acyl acceptor (Scheme 5.19) [38]. [Pg.127]

Sometimes, tertiary allylic alcohols interfere with the oxidation of primary and secondary alcohols with PDC, causing low-yielding transformations into the desired aldehydes and ketones.161 Secondary allylic alcohols occasionally suffer oxidative transposition to enones rather than a direct oxidation.162... [Pg.35]

Rather than a direct oxidation to dienone, the secondary alcohol suffers an oxidative transposition to give a mixture of enone and enal. [Pg.36]

This oxidative transposition of tertiary allylic alcohols into enones or enals is carried out under mild conditions and has ample application in organic synthesis. Although, it can be carried out with other chromium-based reagents (see pages 16 and 35), PCC is the reagent of choice.272... [Pg.56]

Of course, using excess of PCC allows the operation of both, an oxidative transposition of a tertiary allylic alcohol and a normal oxidation of a primary or a secondary alcohol.276... [Pg.57]

The oxidation with PCC causes both, a normal oxidation of the primary alcohol and an oxidative transposition of the tertiary allylic alcohol. [Pg.57]

A recently published full account of another synthesis [69] of the same alkaloid starting from the /rans-cinnamic ester 264 represented a different approach (ACD -> ACDB) to ( )-lycorine (Scheme 42). An intramolecular Diels-Alder reaction of 264 in o-dichlorobenzene furnished the two diastereomeric lactones 265 (86%) and 266 (5%) involving the endo and exo modes of addition respectively. The transposition of the carbonyl group of 265 to 267 was achieved by reduction with lithium aluminium hydride, followed by treatment of the resulting diol with Fetizon s reagent, which selectively oxidised the less substituted alcohol to give isomeric 5-lactone 267. On exposure to iodine in alkaline medium 267 underwent iodolactonisation to afford the iodo-hydroxy y-lactone 268. The derived tetrahydropyranyl ether... [Pg.503]


See other pages where Transposition of alcohol and is mentioned: [Pg.322]    [Pg.512]    [Pg.516]    [Pg.643]    [Pg.643]    [Pg.671]    [Pg.168]    [Pg.322]    [Pg.512]    [Pg.516]    [Pg.643]    [Pg.643]    [Pg.671]    [Pg.168]    [Pg.10]    [Pg.631]    [Pg.6]    [Pg.257]    [Pg.347]    [Pg.272]    [Pg.1065]    [Pg.218]    [Pg.116]    [Pg.93]    [Pg.1065]    [Pg.561]    [Pg.1337]    [Pg.10]    [Pg.486]    [Pg.1065]    [Pg.188]    [Pg.48]    [Pg.616]    [Pg.621]    [Pg.79]   


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ALCOHOL TRANSPOSITION

Transposition

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