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Book British Reports Translations and Theses

Download or read book British Reports Translations and Theses written by British Library. Lending Division and published by . This book was released on 1985 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Methodologies of Bicyclo 2 2 2 octane Compounds and Progress Toward the Total Synthesis of Parthenolide

Download or read book Methodologies of Bicyclo 2 2 2 octane Compounds and Progress Toward the Total Synthesis of Parthenolide written by Courtney Arielle Roberts and published by . This book was released on 2016 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Chapter 1, rearrangements of 4-substituted bicyclo[2.2.2]oct-2-enyl-5-selenophenyl esters are explored. Reduction of the esters under radical-generating conditions initially generates a bicyclo[2.2.2]oct-5-en-2-yl radical which can rearrange to a bicyclo[3.2.1]oct-6-en-2-yl radical via a cyclopropylcarbinyl radical. Although the bicyclo[3.2.1]octene system exhibits greater strain than does the bicyclo[2.2.2]octene system, radical-stabilizing substituents can reverse this preference. The product ratios are influenced by the interplay of ring strain and radical stability. In addition, the rearranged products favored the equatorial over the axial isomers, which can be explained by torsional steering. In Chapter 2, different approaches to the synthesis of the optically active bicyclo[2.2.2]octane-2,5-diones are presented. A stereoselective Diels-Alder cycloaddition was explored to construct the bicyclo[2.2.2]octane skeleton in an efficient manner. This approach was hindered by unexpected polymerization and lack of stereoselectivity. A different method of synthesizing the optically active bicyclo[2.2.2]octane-2,5-dione featuring a diastereoselective 1,4-addition is also presented. In Chapter 3, progress toward the total synthesis of parthenolide is described. The synthetic route relies on ring-closing metathesis to close the 10-membered carbocycle of the natural product. The efforts leading up to and including the key ring-closing step are described. Specific attention is given to different methods for overcoming the difficulties associated with medium-sized ring formation.

Book Some Compounds Related to Bicyclo 3 2 1 Octane

Download or read book Some Compounds Related to Bicyclo 3 2 1 Octane written by William Elmore Gardner and published by . This book was released on 1956 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Bicyclo 2 2 2 Octane

Download or read book Bicyclo 2 2 2 Octane written by Peter J. Day and published by . This book was released on 1984 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The BRITS Index Subject index

Download or read book The BRITS Index Subject index written by British Theses Service and published by . This book was released on 1989 with total page 1156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Studies Towards the Synthesis of Optically Active Bicyclo 2 2 2 octa 2 5 dienes

Download or read book Studies Towards the Synthesis of Optically Active Bicyclo 2 2 2 octa 2 5 dienes written by Breeyawn Nycole Lybbert and published by . This book was released on 2012 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optically active 2,5-disubstituted bicyclo[2.2.2]octa-2,5-dienes (bod) have found use within synthetic organic chemistry as chiral ligands for rhodium asymmetric catalysis reactions. These chiral ligands often provide greater enantioselectivity than their phosphorus-based chiral ligand cousins when employed in the formation of carbon-carbon bonds under rhodium catalysis. The drawback to using these types of 2,5-disubstituted bicyclo[2.2.2]octa-2,5-diene ligands is that they are very expensive to buy if they are commercially available or they must be synthesized if they are not commercially available. Present literature syntheses of these bod ligands rely on the physical separation of diastereomeric derivatives via recrystallization with low recovery or the separation of enantiomers via chiral HPLC, in which only small amounts of material may be separated. We have devised a synthesis of phenyl, benzyl, and methyl substituted bod ligands based on a bridged Robinson annulation reaction of 1,5-diketones and 1,5-ketoaldehydes, which gives the bicyclic core necessary for the bod ligand. Furthermore, our synthesis is designed to create optically active 1,5-diketones and 1,5-ketoaldehydes which transfer their chirality to the bicyclic core of the molecule. Our synthesis does not rely upon separation of racemic material at any step; instead we provide a method to synthesize any optically active bod ligand that is desired. We successfully synthesized the chiral 3-allylcyclohexanone (>95% ee), a key intermediate in our synthesis, using a chiral conjugate allylation of & alpha;, & beta;-unsaturated & beta;-ketoesters using Cu(OTf)2 and the chiral tBu-box ligand. We then successfully completed the racemic synthesis of 2,5-diphenylbicyclo[2.2.2]octa-2,5-diene (Ph-bod) over 11 steps in 4.4% yield. The chiral Ph-bod ligand is projected to take 14 steps and proceed in a 1.1% overall yield. We also synthesized the racemic 2,5-bis(phenylmethyl)bicyclo[2.2.2]octa-2,5-diene (Bn-bod) over 7 steps in 1.4% overall yield. The synthesis of 2,5-dimethylbicyclo[2.2.2]ocat-2,5-diene (Me-bod) was attempted but was unsuccessful at this time. Ultimately we proved the utility of the bridged Robinson annulation reaction for the synthesis of various bicyclo[2.2.2]octa-2,5-dienes.

Book The Patern B chi Reaction

    The Patern B chi Reaction

    Book Details:
  • Author : Maurizio D’Auria
  • Publisher : Cambridge Scholars Publishing
  • Release : 2019-07-29
  • ISBN : 1527537625
  • Pages : 613 pages

Download or read book The Patern B chi Reaction written by Maurizio D’Auria and published by Cambridge Scholars Publishing. This book was released on 2019-07-29 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book represents the most complete description of the scientific results obtained on a photochemical experiment described 110 years ago by the Italian scientist Emanuele Paternò. This detailed that the photochemical reaction between a carbonyl compound and an alkene gives a corresponding oxetane. This oxetane ring is present in several naturally occurring compounds and bioactive compounds, and can be obtained with high regio- and stereoselectivity.

Book Studies in the Bicyclo 2 2 2 octane Series

Download or read book Studies in the Bicyclo 2 2 2 octane Series written by J. Colonge and published by . This book was released on 19?? with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Part One

Download or read book Part One written by Albert C. Kovelesky and published by . This book was released on 1962 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Synthesis and Properties of 1 substituted Bicyclo 2 2 2 Octanes

Download or read book The Synthesis and Properties of 1 substituted Bicyclo 2 2 2 Octanes written by Adnan Abdul-Rida Sayigh and published by . This book was released on 1952 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Synthesis and Reactions of Inside outside Bicyclic Compounds

Download or read book The Synthesis and Reactions of Inside outside Bicyclic Compounds written by Rebecca Cowan Hoye and published by . This book was released on 1981 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: