Scissions sigmatropiques d'acétals non saturés

Mutterer, Francis; Morgen, J. M.; Biedermann, Jean-Michel; Fleury, Jean‐Pierre; Weiss, Francis Joseph

doi:10.1016/s0040-4020(01)97844-5

Cited by 14 publications

(4 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…lo) The thermal retro-ene-reactions of various ally1 acetals have been described by Fleury et al [9].…”

mentioning

confidence: 97%

The Total Synthesis of (±) β‐Acorenol. Preliminary communication

Oppolzer¹

1973

Helvetica Chimica Acta

View full text Add to dashboard Cite

Preliminary Communication2)Zusammmfassung. Die erste Totalsynthesc des Spiro-scsquiterpenes P-Acorenol, ausgehend vom bekanntcn Cyclohex-1-enylessigsaureathylester, wird beschrieben. Die Schliisselstufe 2 + 3 + 4 verlauft iiber eine thermische intramolekulare En-Reaktion ,&Acorenol, a spirocyclic sesquiterpene, isolated from the wood of Juni;6eyus rigida has been shown by chemical and spectroscopic evidence [l] to have structure SS). This communication describes the first total synthesis of racemic ,L?-acorenol 8 and 8-acoradiene 9 [l], the key step of which utilizes recent observations on the stereocontrolled synthesis of five-membered ring systems [4] 4 ) .The known ethyl cyclohex-1-ene-1-acetate 1 [5] was alkylated [6] with l-bromo-3-butene to give the oily diene 25) 6, (b.p. 91-92"/0.3 Torr; IR. : 1730 cm-I). The latter cyclized in toluene (19% solution in a sealed ampoule) at 280" with 3 days') to a 1:l mixture (65% yield) of the esters 35)6) and 45)6), which were separated by l) 2, 4, 5, 6 , ' ) Presented in part at the International Symposium: tNeue Methoden der Organischen Synthese)), Basle, Switzerland, May 11, 1973. The content of this communication will appear as part of a full paper in this journal. For isolation and structure of the closely related alaskenes see [2]. For previous approaches to acorane-type compounds see [3] [8]. The IR.-and NMR.-spectra were in agreement with the assigned structurc. Satisfactory elemental analytical data were obtained for this substance. 1-(5-methyl-4-hexenyl)-cyclohexene is reported not to cyclize at temperatures up to 500" [7].

show abstract

“…lo) The thermal retro-ene-reactions of various ally1 acetals have been described by Fleury et al [9].…”

mentioning

confidence: 97%

The Total Synthesis of (±) β‐Acorenol. Preliminary communication

Oppolzer¹

1973

Helvetica Chimica Acta

View full text Add to dashboard Cite

show abstract

“…Propionaldehyde diallyl acetal (3b) was prepared from propionaldehyde, allyl alcohol and CaCl 2 , as described by Mutterer et al 24 Propionaldehyde di(nitrobenzyl) acetal (3c) and propionaldehyde di(trichloroethyl) acetal (3d) were prepared from propionaldehyde, the requisite alcohol, and toluenesulfonic acid, using the method of Schilling et al 25 1,1-Diacetoxypropane (3e) was prepared from propionaldehyde, acetic anhydride, and FeCl 3 , using the method of Kochbar et al 26 Ethyl 2-acetyloxy-3-bromo-2-propenonate (7) was prepared by the method of Fryzuk et al 13 3-Chloro-1-phenylpropan-1-ones (11a-c) were prepared by reaction of 3-chloropropionyl chloride and aluminium trichloride with the appropriate monosubstituted benzene, and were isolated in 75-82% yield. Phenyl vinyl ketone (6) was prepared by elimination of 3-chloro-1-phenylpropan-1-one (11a) in the presence of triethylamine, in 92% yield.…”

Section: Experimental Materialsmentioning

confidence: 99%

Synthetic 6-aryl-2-hydroxy-6-ketohexa-2,4-dienoic acid substrates for C–C hydrolase BphD: investigation of a general base catalytic mechanism

et al. 2004

View full text Add to dashboard Cite

A chemical synthesis of the 2-hydroxy-6-ketohexa-2,4-dienoic acid intermediates on bacterial meta-cleavage pathways has been established, using a Heck coupling strategy. Coupling of ethyl 3-bromo-2-acetoxyacrylate with 1-aryl vinyl ketals or 1-aryl allylic alcohols proceeded in 70-90% yield. Heck coupling with an alkyl vinyl ketal was also successful, allowing the synthesis of an alkyl-substituted ring fission intermediate. The synthetic ring fission intermediates were used to investigate the enzymatic reaction catalysed by C-C hydrolase BphD from Pseudomonas LB400. A reduced substrate analogue 2,6-dihydroxy-6-phenylhexa-2,4-dienoic acid was processed enzymatically to benzaldehyde by C-C hydrolase BphD, consistent with a catalytic mechanism involving general base-catalysed attack of water to give a gem-diol intermediate, and not consistent with a nucleophilic mechanism. A series of para-substituted 2-hydroxy-6-keto-6-phenylhexa-2,4-dienoic acid substrates were assayed against BphD, and the derived Hammett plot (rho=-0.71) is consistent with a departing carbanion in the transition state for C-C cleavage.

show abstract

“…a,p-Unsaturated aldehydes are also obtained on thermal decomposition of diallyl acetals of alkenals. 191 The thermolysis of 2-(l-alkenyl)-5-alkyl-l,3-dioxanes 191 and 2-(2-alkenyl)-5-methylene-l,3-dioxanes leads to tx,P-unsaturated aldehydes. 193 Acrolein is formed together with acetic anhydride in the catalytic thermolysis of 3,3-diacetoxypropene (and also 1,3-diacetoxypropane) in the presence of palladium or zinc halides.…”

Section: Thermolysis Of Unsaturated Ethers Acetals Acylals and Othmentioning

confidence: 99%