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Rearrangement compounds

Irradiation of chlorobenzodiazepine oxide 4 in the solid state gives the Schifif base 5, accompanied by the rearranged compounds 6 and 7.237... [Pg.413]

The Mossbauer spectrum of the rearranged compound corresponds with that of a Sn(IV) compound, and the most probable structure appears to be that of a chlorine-bridged dimer. [Pg.23]

Deprotonation of allylic aryl sulfoxides leads to allylic carbanions which react with aldehyde electrophiles at the carbon atom a and also y to sulfur . With benzaldehyde at — 10 °C y-alkylation predominates , whereas with aliphatic aldehydes at — 78 °C in the presence of HMPA a-alkylation predominates . When the a-alkylated products, which themselves are allylic sulfoxides, undergo 2,3-sigmatropic rearrangement, the rearranged compounds (i.e., allylic sulfenate esters) can be trapped with thiophiles to produce overall ( )-l,4-dihydroxyalkenes (equation 24). When a-substituted aldehydes are used as electrophiles, formation of syn-diols 27 occurs in 40-67% yields with diastereoselectivities ranging from 2-28 1 (equation 24) . ... [Pg.834]

The reactions of 14 with a-pyrone (17) were carried out at 110 °C and gave the rearranged compound 19 [10b] (Table 2). [Pg.13]

Reaction of dihydropyrrolizine 87 with DMDO in aqueous acetone gives the oxidative rearrangement compound 88 in 59% yield <20030L785>. A plausible mechanism was proposed as shown in Scheme 11. [Pg.14]

Ghloro-l, 2,4-triazino[3,4-Z ]benzothiazoM//-onc 481 gives the rearranged compound 91, with a thiazolo[2,3-c][l,2,4]triazole nucleus, after refluxing with a 10% aqueous solution of NaOH (Equation 111) <1996IJC(B)842>. [Pg.288]

The reaction of [2]paracyclo[2](l,4)naphthalenophane (35) with singlet oxygen in methanol 10° proceeds somewhat differently. In addition to unchanged starting material, the rearranged compound 129 and the cyclization product 130 were detected. [Pg.116]

Anhydroartemisinin (132), a semisynthetic derivative with very high antima-larial activity, was converted to the rearranged compound 136 and to the 9f5-hydroxylated derivative 133 by S. lavendulae L-105, whereas a Rhizopogon species (ATCC 36060) formed hydroxylated metabolites 134 and 135 [2121. Pre-... [Pg.207]

Stereochemical evidence confirms that neither alkyl nor hydride provides anchimeric assistance in the pinacol rearrangement. Compounds 9 and 10 both... [Pg.274]

Various complex products were obtained in reactions of 77 with ketones414. With ben-zophenone, for example, the rearranged compound 85 was obtained, while fluorenone reacted in 2 1 ratio to give 86, both shown in Scheme 24415. Reaction pathways leading to both products were suggested. For additional examples, the original papers should be consulted. [Pg.2553]

Allyl chloride or polychlorinated ethanes with a cleavable C-Cl bond were also investigated thermally (250-290 °C) by Haszeldine et al. [267]. Beside normal and reverse monoadducts produced in poor yields, cyclic or thermal rearranged compounds were obtained. [Pg.201]

Alkylation of 225 with bromoacetone (160) gave the expected product 227, but attempts to cyclize this material gave the rearranged compound 239 (R = H) once more. It was postulated by Dolby et al. that the initially formed product was the desired compound 240 which then rearranged to the observed product 239 (R = C02Et) by the mechanism summarized in Scheme 49. [Pg.80]

When the leaving group is attached to the central carbon atom of a prototropic system, it remains vinylic after the prototropic change. Whereas the substitution in the rearranged compound is not necessarily easier, the product structure may be determined by this rearrangement. [Pg.104]

Thermal degradation of Amadori and Heyns rearrangement compounds. [Pg.430]

In 1988 Gibbs and Okamura [128] described the intramolecular Diels-Alder reaction of the non-racemic vinylallene 150 to afford the adduct 151 (as a mixture of epimers at sulfur) in a completely exo-selective manner, due to the topographical and steric arrangement of the starting vinylallene (Scheme 74). Compound 150 was obtained as a mixture of epimers at sulfur from the optically pure propargylic alcohol 149 (this transformation involved a sulfoxide-sulfenate rearrangement). Compound 151 was used to synthesize (-l-)-sterpurene. [Pg.78]

Dimroth-type rearrangements are well documented in fused pyrimidines such as in [l,2,4]triazolo[4,3-a]pyrimidines and [l,2,4]triazolo[4,3-c]pyrimidines under acid or alkaline conditions. The same type of reaction will occur in pyrimidines fused to azoles containing other heteroatoms. Thus, the pyrimidines (695) undergo the Dimroth reaction under both acid and alkaline conditions to furnish the rearranged compounds (696) (74JOC3783). [Pg.739]

Nal-Zn dust/ Attempted hydrogenolysis of the 5-mesyloxy-3,6-cyclo-A-nor-3,5-secoandrostane (7) with LiAlH4 gave the seco-alcohol (8), whereas with Nal-Zn dust, it gave the rearranged compound (9). ... [Pg.216]

Backbone Rearrangements and Double Bond Isomerizations.—Acid-catalysed (BF3-Et20 or toluene-p-sulphonic acid) rearrangement of A -, A -, and cholestenes gave"° the spiro-olefins (128). An earlier report that a A -olefin gave a partially backbone-rearranged compound was discounted and it was... [Pg.232]

The above results suggest that in the carbocationic process the second 6-endo cyclization is relatively fast but the third 5-exo cyclization is quite slow. Thus, formation of the bicyclic rearranged compound 41 is allowed whereas that of monocyclic products is avoided. In the radical process, however, the second 6-endo cyclization seems to be relatively slow and the third 5-exo cyclization fairly fast, thus allowing the formation of monocyclic achilleol A (9) and avoiding bicyclic products. In other words, there are subtle... [Pg.82]

Group Migration Reactions.—1,3-Fluorine migrations have been reported following the mercury-sensitized irradiation (7 days) of the perfluoroalkenes (17a) and (17b).The products from the reaction are the skeletally rearranged compounds (18). Direct irradiation of the natural product Mortonin C (19) in methanol yielded two photoproducts identified as (20a) and (20b). These... [Pg.278]

Under conditions of thermolysis, photolysis and hydrogenation certain isoxazoles can be converted into imidazoles. For example, merely heating 5-amino-3,4-diaUcylisoxazoles at 180-190°C gives 40-65% yields of 4,5-dialkylimidazolln-2-ones in what initially appears to be a Dimroth-type rearrangement. Compounds such as 4-mcthyl-5-propyl-, 4-butyl-5-propyl, 5-benzyl-4-methyl-, 4,5-dimethyl- and 4-ethyl-5-methylimidazoles can be formed in the same way, but only if urea is present and if the reaction is carried out in the condensed phase. Without the added urea (or an arylamine) the yields are only 40-65% with urea they reach 70-90% [29-31]. [Pg.172]


See other pages where Rearrangement compounds is mentioned: [Pg.834]    [Pg.428]    [Pg.242]    [Pg.154]    [Pg.116]    [Pg.947]    [Pg.73]    [Pg.325]    [Pg.759]    [Pg.464]    [Pg.782]    [Pg.239]    [Pg.32]    [Pg.119]    [Pg.163]    [Pg.774]    [Pg.70]    [Pg.151]    [Pg.151]    [Pg.336]    [Pg.29]    [Pg.213]    [Pg.94]    [Pg.68]    [Pg.188]    [Pg.97]    [Pg.217]    [Pg.823]    [Pg.124]   
See also in sourсe #XX -- [ Pg.253 ]

See also in sourсe #XX -- [ Pg.826 ]

See also in sourсe #XX -- [ Pg.19 ]




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1,2-Anionic Rearrangement of Organosilicon and Germanium Compounds

1,2-Anionic rearrangements organosilicon compounds

1.5- Dicarbonyl compounds via Claisen rearrangement

2,3-Wittig-oxy-Cope rearrangement 8,e-unsaturated carbonyl compounds

Acid-promoted rearrangement carbonyl compounds

Allenyl phosphoryl compounds via rearrangement

Allyl phosphoryl compounds via rearrangement

Allylic nitro compounds rearrangement

Aluminum compounds Claisen rearrangement

Amadori compounds rearrangement

Anionic rearrangement experimental compounds

Aromatic compounds rearrangements

Aromatic nitro compounds rearrangement

Aromatic rearrangements azoxy compounds

Aziridinyl compounds rearrangement

Azoxy compounds rearrangement

Azoxy compounds rearrangement with acid

Benzyloxy compounds, rearrangement

Bicyclic compounds Wagner-Meerwein rearrangment

Boron compounds rearrangement

Bromine compounds, Hofmann rearrangement

Carbon compounds Favorskii rearrangement

Carbon compounds pinacol rearrangement

Carbon compounds skeletal rearrangement

Carbonyl compounds from Claisen rearrangement

Carbonyl compounds rearrangement reactions

Carbonyl compounds rearrangements

Chiral compounds 2,3]-Wittig rearrangement

Chiral compounds 3,3]-sigmatropic rearrangement

Claisen rearrangements compounds

Claisen rearrangements, in nitrogen compounds

Cluster compounds rearrangements

Cycloaddition and Rearrangement Reactions of Unsaturated Carbonyl Compounds

Diazo compounds decomposition with rearrangement

Diazo compounds rearrangements involving

Diazocarbonyl compounds rearrangement

Diene compounds Cope rearrangement

Electrocyclic rearrangements compounds

Ester compounds, Favorskii rearrangement

Heterocyclic compounds 3,3]-sigmatropic rearrangements

Heterocyclic compounds Dimroth rearrangement

Heterocyclic compounds rearrangement

Hydrazo compounds rearrangement

Isomerization, Rearrangement, and Redistribution of Alkylmetal Compounds

Methane Rearrangement in Natural Compounds

NQR in Molecular Compounds and Intramolecular Rearrangement

Neopentyl compounds rearrangement

Neophyl compounds rearrangement

Nitro compounds rearrangement

Nitrobenzyl compounds rearrangement

Nitrogen compounds Curtius rearrangement

Nitrogen compounds Stevens rearrangement

Olefinic compounds, rearrangements

Organoboron compounds rearrangement

Organocopper compounds rearrangement

Organogold compounds rearrangement

Organolithium compounds rearrangement

Organolithium compounds rearrangement reactions

Organomagnesium compounds rearrangement

Organomagnesium rearrangements allylic compounds

Organometallic compounds complex rearrangement

Organopalladium compounds rearrangement

Organotin compounds rearrangement

Organozinc compounds in Claisen rearrangement of allylic alcohols

Organozinc compounds rearrangement

Organozinc compounds rearrangement reactions

Phosphorus compounds, pentavalent turnstile rearrangement and

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudoration

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudoration in permutational

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudoration in permutational isomerization

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudoration permutational isomerization

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudorotation

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudorotation in permutational isomerization

Phosphorus compounds, pentavalent, turnstile rearrangement and pseudorotation permutational isomerization

Polymerisation and Rearrangement in Compounds with Multiple Bonds

Propargylic compounds rearrangement

Rearrangement 1,2-disubstituted compounds

Rearrangement diazo compounds

Rearrangement during reaction of halogen compounds

Rearrangement ketone/aldehyde compounds

Rearrangement of Allylic Organomagnesium Compounds

Rearrangement of Oxaspiro Compounds

Rearrangement of halogen compounds

Rearrangement on decomposition of diazo compounds

Rearrangement reaction with aromatic compounds

Rearrangements cage compounds

Rearrangements of Organoaluminum Compounds and Their Group II Analogs

Rearrangements of Unsaturated Organoboron and Organoaluminum Compounds

Rearrangements organoaluminum compounds

Rearrangements reaction with organocopper compounds

Rearrangements to Spiro Compounds

Rearrangements unsaturated carbonyl compounds

Reissert compounds rearrangements

Schmidt Rearrangements of Hydroxyalkyl Azides toward Biologically Relevant Compounds

Sigmatropic Rearrangement of Propargyl Compounds

Silver compounds rearrangement

Smiles rearrangement, carbonyl compounds

Spiro compounds rearrangement

Sulphinyl compounds rearrangement

Thiocarbonyl compounds Thio-Claisen rearrangement

Thiocarbonyl compounds rearrangement

Tricyclic compounds Cope rearrangements

Triphenylmethyl compounds rearrangement

Turnstile rearrangements in isomerization of pentavalent phosphorus compounds

Unsaturated compounds Claisen rearrangement

Wittig rearrangement compounds

Wolff rearrangements diazo compounds

Wolff rearrangements diazocarbonyl compounds

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