Author: Jeffrey C. H. DyckPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Versatility and Utilization of Phosphorus Based Compounds in Classic Carbon-carbon Bond Forming and Esterification Reactions
Author: Jeffrey C. H. DyckSynthesis of Carbon-Phosphorus Bonds
Author: Robert EngelPublisher: CRC Press
ISBN: 0203998243
Category : Science
Languages : en
Pages : 200
Book Description
Synthesis of Carbon-Phosphorus Bonds, Second Edition is a working guide for the laboratory, incorporating classical approaches with the recent developments of carbon-phosphorus (C-P) bond formation. These advances include the preparation of phosphoranes - specifically in the use of transient oxophosphoranes as intermediates in organophosphorus comp
Carbon-Carbon ?-Bond Formation
Author: G. PattendenPublisher: Elsevier
ISBN: 008091246X
Category : Science
Languages : en
Pages : 1209
Book Description
Volume 3 covers carbon-to-carbon single bond forming reactions involving sp3, sp2 and sp carbon centers, but only those which do not involve additions to C-X &pgr;-bonds. The volume first compares and contrasts the alkylation reactions of all types of sp3 carbon nucleophiles and also covers vinyl and alkynyl carbanions. Following on from Volume 2, a separate section covers Friedel-Crafts alkylation reactions, which is complemented by discussions of polyene cyclizations and electrophilic transannular cyclizations in synthesis. Coupling reactions leading to &agr;-bond formation, and involving all types of combinations ofsp3, sp2 and sp carbon centers are next covered, including those reactions based on pinacol, acyloin and phenol oxidative coupling reactions, and also the Kolbe reaction. Rearrangement reactions, leading to carbon-to-carbon &agr;-bond formation, are often used in a clever manner in synthesis. The volume includes all those rearrangement reactions based on intermediate carbonium ions and carbanions, and also includes the benzil-benzilic acid and the Wolff rearrangements. The volume closes with coverage of carbonylation reactions, and the use of carbene insertion reactions into the C-H bond in synthesis.
Synthesis of Carbon-Phosphorus Bonds, Second Edition
Author: Robert EngelPublisher: CRC Press
ISBN: 9781135502034
Category : Science
Languages : en
Pages : 200
Book Description
Synthesis of Carbon-Phosphorus Bonds, Second Edition is a working guide for the laboratory, incorporating classical approaches with the recent developments of carbon-phosphorus (C-P) bond formation. These advances include the preparation of phosphoranes - specifically in the use of transient oxophosphoranes as intermediates in organophosphorus compound synthesis ñ along with the new approaches towards the preparation of compounds with aromatic and vinylic C-P bonds. Synthesis of Carbon-Phosphorus Bonds, Second Edition serves as a useful tool in the laboratory. It offers detailed surveys of IUPAC nomenclature recommendations, common notation systems, and various experimental examples. These features help to make this text an effective source of critical and annotated references, as well as a a working guide for organic and phosphorus chemists specifically, or for any chemists working with C-P bonds.
New Reactions and Reagents for Phosphorus-carbon Bond-formation
Author: Michael B. GeesonPublisher:
ISBN:
Category :
Languages : en
Pages : 373
Book Description
Chapter 1 takes the format of an "Outlook", and sets forth the case for developing sustainable methods in the synthesis of phosphorus-containing compounds. Methods used by nature for phosphorus-carbon bond-formation, or in the chemistry of other elements such as silicon, are discussed as model processes for the future of phosphorus in chemical synthesis. Chapter 2 describes the discovery of [TBA][P(SiCl3)2], prepared from [TBA]3[P3O9]-.2H2O and trichlorosilane. The bis(trichlorosilyl)phosphide anion is used to prepare compounds that contain P–C, P–O, P–F, and P–H bonds in a method that bypasses white phosphorus (P4), the traditional route to organophosphorus compounds. Chapter 3 extends the phosphate precursors to [TBA][P(SiCl3)2] from trimetaphosphate to crystalline phosphoric acid. Balanced equations are developed for the formation of [TBA][P(SiCl3)2] from phosphate sources and the byproducts are identified as hexachlorodisiloxane and hydrogen gas. Extension of trichlorosilane reduction to bisulfate provides improved access the known trichlorosilylsulfide anion, [TBA][SSiCl3]. This anion was used as a thionation reagent to prepare thiobenzophenone and benzyl mercaptan from benzophenone and benzyl bromide, respectively. Chapter 4 describes the synthesis of neutral phosphine, HP(SiCl3)2, obtained by protonation of [TBA]1 with triflic acid. HP(SiCl3)2 is a highly efficient reagent for photochemical hydrophosphination of terminal alkenes. The phosphorus-silicon bonds in the hydrophosphination products can be functionalized to provide compounds of the general formulae: RPCl2, RPH2, [RP(R')3]Cl, RP(O)(H)(OH), and RP(O)(OH)2. Chapter 5 describes a method to prepare phosphiranes (three-membered rings that contain a phosphorus atom) from anthracene-based phosphinidene precursors and styrenic olefins. The phosphinidene transfer reaction requires an organoiron and fluoride catalyst. The resulting phosphirane is prepared in good yield (73%) with high stereoselectivity (>99%). Experimental investigations into the mechanism point toward the intermediacy of an iron-coordinated fluorophosphide species.
Stereoselective Carbon-carbon Bond Forming Reactions Using Chiral Phosphorus(v) Compounds and the Derived Anions
Author: Jung Ho KimPublisher:
ISBN:
Category :
Languages : en
Pages : 754
Book Description
C$sb2$-Symmetric diamines were synthesized in order to examine carbon-carbon bond forming reactions using chiral auxiliary-based phosphorus reagents. The general utility of these diamines as chiral auxiliaries in the diastereoselective alkylation of P-alkyl anions was examined. A systematic study of the alkylation of the P-alkyl anions was accomplished varying N-alkyl and P-alkyl substituents. High diastereoselectivity was achieved with N-neopentyl substrates (up to 92:8 diastereoselectivity). The P-allyl anions with varying phosphorus substituents have heen investigated. The diastereoselectivity and the regioselectivity of Michael reactions of chiral cis-oxazaphosphorinanes with cyclic enones were very high. The reaction with chiral trans-oxazaphosphorinanes was not selective. The conjugate addition reaction of a variety of P-allyldiazaphosphorinanes with cyclic enones, varying the substituent of P-allyl unit, was highly regio- and diastereoselective. The nucleophilic addition to the $alpha,beta$-unsaturated phosphorus(V) compounds proved to be highly nucleophile-dependent. The nucleophiles with certain range of pK$sb{rm a}$ values (25-32) have been shown to react with the $alpha,beta$-unsaturated phosphorus(V) compounds. The diastereoselectivity of the reaction with sulfone stabilized anions or the amide enolates was low in either the internal or relative sense due to the flexible conformation of the P-propenyl side chain. The general reactivity of P-acyl enolate was extraordinarily low toward usual electrophiles except for silylating agents (TMSCl, TESCl) which produced (E)-silyl enol ethers exclusively. Asymmetric aldol reaction of the enolates derived from P-acylphosphorus heterocycles were not highly successful (up to 36% e.e.) mostly due to their low reactivity and the nature of the thermodynamically controlled reaction.
Carbon-phosphorus and Oxygen-phosphorus Bond Formation
Author: Henry C. FisherPublisher:
ISBN:
Category : Chemical bonds
Languages : en
Pages :
Book Description
The work in this dissertation deals with the continued development of new methodologies for P-C and P-O bond formation using alternative methods that avoid the use of PCl3. A review of the relevant literature that proceeds this work is presented in Chapter 1. Chapter 2 describes the study of the P(III) to P(V) tautomerization of phosphinylidene compounds and the structural influences that effect the thermodynamic and kinetic properties to favor the more reactive P(III) species. A collaboration using both computational and experimental methods, show that electron withdrawing groups such as phenyl stabilize the tautomerization of phosphinylidene compounds. The second part of this work highlights the influence of various catalysts on P(III) to P(V) tautomerization. Using computational chemistry as a screening tool, a variety of organic acids and bases were tested. The calculations and experimental results are in good agreement. Chapter 3 describes the work to develop the nickel-catalzyed hydrophosphinylation of unactivated alkenes, an extension of the work started with the nickel-catalyzed hydrophosphosphinylation of alkynes. The results show that nickel chloride is pre-activated to an active Ni(0) species and can be stabilized by the inexpensive bisphosphine ligand, ethylbis(diphenylphosphine), dppe. The reaction occurs at room temperature and works on a variety of different alkene substrates. Other manipulations used in tandem with the initial nickel hydrophosphinylation are highlighted, and show the reaction to be a versatile tool for making alkyl-H-phosphinate derivatives as precursors for further use. Chapter 4 details the development of manganese-promoted intermolecular and intramolecular additions of alkenes, alkynes and aryl compounds with H-phosphinates is described. The system utilizing catalytic Mn(OAc)2 either neat or in DMSO, is successful for a variety of different alkenes and two alkyne substrates. A more efficient and cost-effective system was recently developed for H-phosphinate arylations using catalytic Mn(OAc)2 and MnO2 as an oxidant, and further applied to alkene phosphonochlorination with LiCl. In Chapter 5, nickel-catalyzed oxidation of alkyl hypophosphites is utilized to prepare ubiquitous alkyl-H-phosphonates starting from hypophosphorous acid and avoiding the use of PCl3. The reaction can be considered a form of water splitting. The studies show that after the intitial esterification step, NiCl2 or Ni/SiO2 is enough to oxidize the first P-H bond to form the desired phosphonate. The reaction has been applied to the synthesis of the global herbicide glyphosate.
Carbon-carbon Bond Formation
Author: Robert L. AugustinePublisher: CRC Press
ISBN: 9780824767877
Category : Science
Languages : en
Pages : 480
Book Description
Phosphorus Chemistry
Author: Yufen ZhaoPublisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110562456
Category : Science
Languages : en
Pages : 182
Book Description
The book is the first thorough study of the role of phosphorus chemistry in the origin of life. This book starts with depiction of the phosphorus role in life creation and evolution. Then it outlines in vital processes how different phosphorus-containing compounds participate as biomarker in life evolution. Written by renowned scientists, it is suitable for researchers and students in organic phosphorus chemistry, biochemistry and etc.
Phosphorus: The Carbon Copy
Author: Keith B. DillonPublisher: John Wiley & Sons
ISBN:
Category : Science
Languages : en
Pages : 704
Book Description
Phosphorus: The Carbon Copy examines the extraordinary similarity between low coordinate phosphorus compounds and unsaturated carbon compounds. Written by three of the leading researchers in the field of modern phosphorus chemistry, Phosphorus: The Carbon Copy focuses on the interface between phosphorus and the transition metal elements and deals with the most recent aspects of unsaturated organophosphorus compounds and their coordination chemistry. Aimed at graduate students as well as academic and industrial researchers, this concise volume publicisies the extraordinary potential of these new phosphorus compounds for applications in catalysis, molecular materials and biochemistry.