1119-60-4Relevant articles and documents
INTRAMOLECULAR CYCLOADDITION AND SEQUENTIAL RING EXPANSION
Zhang, Wei,Collins, Michael R.,Mahmood, Khalid,Dowd, Paul
, p. 2729 - 2732 (1995)
Free radical expansion of fused-cyclobutanones gives bicyclic ketones expanded by three and four carbons, with the carbonyl group β to the ring junction.Four-carbon ring expansion shows stereoselectivity favoring the trans-fused product 6-trans.The radical precursor cyclobutanones are readily prepared by intramolecular cycloaddition of ketenes or keteniminium salts to olefins.
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Lamb,R.C.,Ayers,P.W.
, p. 1441 - 1442 (1962)
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A short synthesis of (±)-alloyohimbane via a thioisomunchnone based intramolecular dipolar-cycloaddition reaction
Heidelbaugh, Todd M.,Liu, Bing,Padwa, Albert
, p. 4757 - 4760 (1998)
Thioisomunchnone dipoles were generated by the reaction of bromoalkenoyl chlorides with thioamides. The intramolecular dipolar-cycloaddition reaction was used for a short synthesis of the yohimbanoid alkaloid (±)- alloyohimbane.
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Israeli,M.,Pettit,L.D.
, p. 414 - 417 (1975)
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Jenkins,C.L.,Kochi,J.K.
, p. 3103 - 3111 (1971)
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Experimental determination of the activation parameters and stereoselectivities of the intramolecular Diels-Alder reactions of 1,3,8-nonatriene, 1,3,9-decatriene, and 1,3,10-undecatriene and transition state modeling with the Monte Carlo-Jumping between Wells/molecular dynamics method
Diedrich, Matthias K.,Kl?rner, Frank-Gerrit,Beno, Brett R.,Houk,Senderowitz, Hanoch,Still, W. Clark
, p. 10255 - 10259 (1997)
Experimental activation parameters for the intramolecular Diels-Alder reactions of 1,3,8-nonatriene, 1,3,9-decatriene, and 1,3,10-undecatriene have been measured, and the Monte Carlo-Jumping between Wells/Stochastic Dynamics [MC(JBW)/SD] method, which gives relative free energies of activation, was tested as a means to predict stereoselectivities. The predictions are compared to experimental results, and to predictions from quantum and molecular mechanics methods.
A Highly Catalytic and Selective Conversion of Carboxylic Acids to 1-Alkenes of One Less Carbon Atom
Miller, Joseph A.,Nelson, Jeffrey A.,Byrne, Michael P.
, p. 18 - 20 (1993)
An equimolar mixture of a carboxylic acid and acetic anhydride produces a reagent combination that undergoes a highly efficient decarbonylation/dehydration at 250 deg C using either Pd- or Rh-based catalyst systems, affording excellent yields of the corresponding 1-alkenes of one less carbon atom.
New alkaloidal metabolites from cultures of entomopathogenic fungus Cordyceps takaomontana NBRC 101754
Hama, Maichi,Elshamy, Abdelsamed I.,Yoneyama, Tatsuro,Kasai, Yusuke,Yamamoto, Hirohumi,Tanigawa, Kana,Oshiro, Ayari,Noji, Masaaki,Ban, Sayaka,Imagawa, Hiroshi,Umeyama, Akemi
, (2019)
Two new alkaloidal metabolites, cordytakaoamides A (1) and B (2), as well as, 2-[(2-hydroxyethyl) amino] benzoic acid (3) and 2E-decenamide (4), and three known compounds (5–7) were isolated from ethyl acetate and n-butanol soluble portions of the entomopathogenic fungus, Cordyceps takaomontana NBRC 101754. Compounds 3 and 4 were isolated here for first time from natural resources. The chemical structures were established depending upon spectroscopic techniques such as 1D, 2D NMR, and HRMS. The absolute configuration of 1 and 2 was elucidated via the total synthesis of 1 as well as the experimental circular dichroism. Compound 3 was confirmed by a signal crystal X-ray analysis.
Ni-Catalyzed β-Alkylation of Cyclopropanol-Derived Homoenolates
Mills, L. Reginald,Zhou, Cuihan,Fung, Emily,Rousseaux, Sophie A. L.
supporting information, p. 8805 - 8809 (2019/11/03)
Metal homoenolates are valuable synthetic intermediates which provide access to β-functionalized ketones. In this report, we disclose a Ni-catalyzed β-alkylation reaction of cyclopropanol-derived homoenolates using redox-active N-hydroxyphthalimide (NHPI) esters as the alkylating reagents. The reaction is compatible with 1°, 2°, and 3° NHPI esters. Mechanistic studies imply radical activation of the NHPI ester and 2e β-carbon elimination occurring on the cyclopropanol.
Low catalyst loading in ring-closing metathesis reactions
Kadyrov, Renat
supporting information, p. 1002 - 1012 (2013/02/23)
An efficient procedure is described for ring-closing metathesis reactions. A conversion of 95 % for diethyl diallylmalonate in dilute solution could be achieved within a few minutes, reaching TOF=4173min-1, with very low loading of commercially available Ru catalysts that contained unsaturated NHC ligands. In general, only 50 to 250ppm of the catalyst is required to achieve near-quantitative conversion into a broad variety of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-tert-butoxycarbonyl (N-Boc)- and N-para-toluenesulfonyl (N-Ts)-protected cyclic amines and 9-16-membered lactones. The synthesis of macrocyclic proline-based lactams required slightly higher catalyst loadings. Along with monocyclic products, oligomeric byproducts, mostly cyclodimers, were isolated and characterized. Getting some closure: An efficient procedure is described for ring-closing metathesis reactions in which only 50 to 250ppm of catalyst is required to effect almost-quantitative conversion into a broad range of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-protected cyclic amines, 9-16-membered lactones, and 11-16-membered proline-based lactams. Copyright
