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Showing 1 to 20 of 72 for “"nucleophilic substitution"”.
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Studies of Nucleophilic Substitution at Neutral Nitrogen
The mechanism of nucleophilic substitution at a formally neutral nitrogen has been investigated. The two limiting mechanisms are a concerted reaction in which the transition state has the nucleophile and leaving group associated with nitrogen and an ionization process involving the initial …
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A STUDY OF ENDOCYCLIC NUCLEOPHILIC SUBSTITUTION AT SULFUR(VI) (SULFONATE ESTERS)
<p>To investigate the effect of geometry on nucleophilic substitution at sulfur (VI), a search was made for examples of endocyclic substitution. Substrate molecules were synthesized and then treated with strong bases, n-butyllithium or lithium diisopropylamide, in order to deprotonate a nitrogen or …
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The effect of methyl groups on nucleophilic substitution reactions of chlorocyclotriphosphazenes
… The results allow a new interpretation of the substitution patterns of various nucleophiles on chlorocyclotriphosphazenes.
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The endocyclic restriction test: (I) Determination of reaction pathways for the nucleophilic substitution at phosphorus by carbon. (II) Exploration of the reaction pathway of nucleophilic substitution at an oxenoid oxygen by carbon
… alkoxy leaving group is suggested for these nucleophilic substitutions at phosphorus.
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The Geometry of Formal Nucleophilic Substitution at Nonstereogenic Atoms: Use of the Endocyclic Restriction Test
The geometry of formal nucleophilic substitution at the nonstereogenic atoms, oxygen, nitrogen, and chlorine has been investigated by use of the endocyclic restriction test.
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Studies of Nucleophilic Substitution in Hindered Aromatic Ketones. A New Route to the Ortho-Terphenyls
Made available in DSpace on 2014-12-05T19:36:57Z (GMT). No. of bitstreams: 1 5900464.pdf: 4726768 bytes, checksum: 0565ae1c2f55ab7832edd7daf0c21a8a (MD5) Previous issue date: 1958
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Geometrical Requirements for Nucleophilic Substitution at Bivalent sulfur(II) and sulfur(VI): An Application of the Endocyclic Restriction Test
Embargo set by: Seth Robbins for item 85782 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs
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Approaches to the study of the geometry and mechanisms of nucleophilic substitution at oxygen, sulfur (II), and chlorine: Applications of the endocyclic restriction test
Restriction data tranferred 2014-07-01T11:29:25-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission
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PART I: INVESTIGATION OF ENDOCYCLIC NUCLEOPHILIC SUBSTITUTION AT DI- AND TETRA-COORDINATE SULFUR PART II: SYNTHESIS OF 3-TOSYL-1,2,3-BENZOXATHIAZOLE-2,2-DIOXIDE AND ITS REACTIONS WITH NUCLEOPHILES
… which appeared capable of undergoing endocyclic nucleophilic substitution at sulfur, were synthesized. Each compound was treated with the strong base (sodium hydride or n-butyllithium) in THF. No trace of the hoped-for base-induced rearrangement products were found. …
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Aspects of the chemistry of 1,4-naphthoquinones. An investigation of nucleophilic substitution reactions of alkylamines and hydroxyalyklamines on 1,4 napthoquinones and the role of solvent on the position of substitution.
Nucleophilic substitution reactions of alkylamines, cyclic alkylamines, and hydroxyalkylamines with 5-substituted-1,4-naphthoquinones have been studied. It has been found that the nature of the solvent employed in the reaction influences the position of mono-substitution at either the 2- or …
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The Stereochemistry of Organosilicon and Complex Inorganic Compounds: i.a Study of the Mechanism of a Nucleophilic Substitution Reaction on an Organosilicon Compound. Ii. The Partial Resolution of Racemic Propylenediamine Through an Optically Active Complex Inorganic Compound
Made available in DSpace on 2014-12-05T19:35:58Z (GMT). No. of bitstreams: 1 0009096.pdf: 3450031 bytes, checksum: dbde489183679109dfa2241d3b8a5694 (MD5) Previous issue date: 1954
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Synthetic and analytical investigations related to vegetable oils and fats.
… conversion into 1,3-diacylgiycerols by nucleophilic substitution. From the 1,3-diacylglycerols, five symmetrical diacid tnacylglycerois have been prepared by reaction with an appropriate acid chloride. By the silyl ether route symmetrical diacylglycerols have been prepared from the …
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Recent advances in copper- and palladium-catalyzed carbon-heteroatom and carbon-carbon bond-formation
Metal-catalyzed nucleophilic substitution reactions of aryl halides have become one of the most valuable and useful classes of reactions developed in the last 30 years. Foremost among these processes are the classes of palladium- and copper-catalyzed reactions, which employ heteroatom-based …
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Regioselective chlorination of cellulose esters
… leaving group to cellulose backbone, followed by nucleophilic substitution reaction. Though tosylation and bromination of cellulose are frequently used, they have drawbacks such as chemo- and regioselectivity issues, high cost, and difficulty in purification. We have successfully developed a …
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The Sʀɴ1 reactivity of selected aromatic diazines
… and limitations of aromatic diazines undergoing nucleophilic substitution reactions occurring via a radical-chain Sʀɴ1 mechanism were investigated. The study was conducted on a series of mono- and dihalogenated aromatic diazines interacting with various ketone enolates in ammonia. Results …
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Exploiting imidate ligand effects in transition metal-mediated C-C bond forming processes
… in enyne cycloisomerisation and propargylic nucleophilic substitution, diene ring-closing metathesis and ring-opening metathesis polymerisation and direct arylation reactions, respectively, has been determined. [Au(N-imidate)(NHC)] and [AuBr2(N-imidate)(NHC)] complexes were prepared and the …
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Molecularly imprinted nanoparticles to mimic natural enzymes for substrate-selective catalysis
… esters, hydrolysis of glycosides, and doing nucleophilic substitution reactions. By taking advantage of templates, we can regulate the active site's size and shape and install different catalytic groups in the right positions near each other within the active site so that they can collaborate …
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Nucleophilic displacement reactions of some carbohydrates in dimethyl sulphoxide
… of toluene-p-sulphonic acid rather than nucleophilic substitution. The results of the work are presented within the context of possible approaches to converting pentoses into hexoses by way of chain extension reactions at the C-5 carbon atom of pentofuranoses.
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