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Synthetic reactions

These preparations, with those noted in the Preface to the Third Edition, cover a considerable proportion of the standard synthetic reactions. Most of these preparations come towards the end of Part II Preparations), and both elementary and advanced students should have no difficulty in selecting the preparative work they require. [Pg.585]

Ease of Reduction (taken from EI.O. Elouse Modern Synthetic Reactions, 2nd edition)... [Pg.31]

O Most synthetic reactions, which produce carbon-carbon bonds, are polar a negatively... [Pg.1]

The combination ( synthetic reaction) of both synthons would yield ethane. [Pg.1]

Alkyl halides and sulfonates are the most frequently used alkylating acceptor synthons. The carbonyl group is used as the classical a -synthon. O-Silylated hemithioacetals (T.H. Chan, 1976) and fomic acid orthoesters are examples for less common a -synthons. In most synthetic reactions carbon atoms with a partial positive charge (= positively polarized carbon) are involved. More reactive, "free carbocations as occurring in Friedel-Crafts type alkylations and acylations are of comparably limited synthetic value, because they tend to react non-selectively. [Pg.15]

In the synthesis of molecules without functional groups the application of the usual polar synthetic reactions may be cumbersome, since the final elimination of hetero atoms can be difficult. Two solutions for this problem have been given in the previous sections, namely alkylation with nucleophilic carbanions and alkenylation with ylides. Another direct approach is to combine radical synthons in a non-polar reaction. Carbon radicals are. however, inherently short-lived and tend to undergo complex secondary reactions. Escheirmoser s principle (p. 34f) again provides a way out. If one connects both carbon atoms via a metal atom which (i) forms and stabilizes the carbon radicals and (ii) can be easily eliminated, the intermolecular reaction is made intramolecular, and good yields may be obtained. [Pg.36]

The usual base or acid catalyzed aldol addition or ester condensation reactions can only be applied as a useful synthetic reaction, if both carbonyl components are identical. Otherwise complicated mixtures of products are formed. If two different aldehydes or esters are to be combined, it is essential that one of the components is transformed quantitatively into an enol whereas the other component remains as a carbonyl compound in the reaction mixture. [Pg.55]

Most of the synthetic reactions leading to substituted carbon compounds can be re> versed. Reiro-a do or /le/fo-Diels-Alder reactions, for example, are frequently used in the de-gradative fragmentation of complex molecules to give simpler fragments. In synthesis, such... [Pg.88]

Simple compounds are defined here in an unusual but practical way a simple molecule is one, that may be obtained by four or less synthetic reactions from inexpensive commercial compounds. We call a commercial compound inexpensive if it costs less or not much more than one German mark per gram. This also implies, that only those compounds that cannot be purchased inexpensively are considered as synthetic target molecules in this book. [Pg.171]

In this chapter some important synthetic reactions specific to each class of compounds are described. Only small parts of certain total syntheses will be discussed. With the given references, however, the interested reader will easily locate the complete descriptions of the syntheses. I. Fleming s (1973) book is recommended as a guide through some ingenious classic total syntheses. [Pg.215]

In spite of the diverse nature of alkaloid structures, two structural units, i.e. fused pyrrolidine and piperidine rings in different oxidation states, appear as rather common denominators. We therefore chose to give several examples for four types of synthetic reactions which have frequently been used in alkaloid total synthesis and which provide generally useful routes to polycyclic compounds with five- or six-membered rings containing one nitrogen atom. These are ... [Pg.289]

Primary and secondary amines also react with epoxides (or in situ produced episulfides )r aziridines)to /J-hydroxyamines (or /J-mercaptoamines or 1,2-diamines). The Michael type iddition of amines to activated C—C double bonds is also a useful synthetic reaction. Rnally unines react readily with. carbonyl compounds to form imines and enamines and with carbo-tylic acid chlorides or esters to give amides which can be reduced to amines with LiAlH (p. Ilf.). All these reactions are often applied in synthesis to produce polycyclic alkaloids with itrogen bridgeheads (J.W. Huffman, 1967) G. Stork, 1963 S.S. Klioze, 1975). [Pg.291]

In the last fifteen years macrolides have been the major target molecules for complex stereoselective total syntheses. This choice has been made independently by R.B. Woodward and E.J. Corey in Harvard, and has been followed by many famous fellow Americans, e.g., G. Stork, K.C. Nicolaou, S. Masamune, C.H. Heathcock, and S.L. Schreiber, to name only a few. There is also no other class of compounds which is so suitable for retrosynthetic analysis and for the application of modem synthetic reactions, such as Sharpless epoxidation, Noyori hydrogenation, and stereoselective alkylation and aldol reactions. We have chosen a classical synthesis by E.J. Corey and two recent syntheses by A.R. Chamberlin and S.L. Schreiber as examples. [Pg.319]

A rational classification of reactions based on mechanistic considerations is essential for the better understanding of such a broad research field as that of the organic chemistry of Pd. Therefore, as was done in my previous book, the organic reactions of Pd are classified into stoichiometric and catalytic reactions. It is essential to form a Pd—C cr-bond for a synthetic reaction. The Pd— C (T-bond is formed in two ways depending on the substrates. ir-Bond formation from "unoxidized forms [1] of alkenes and arenes (simple alkenes and arenes) leads to stoichiometric reactions, and that from oxidized forms of alkenes and arenes (typically halides) leads to catalytic reactions. We first consider how these two reactions differ. [Pg.13]

When the reaction was earned out m aqueous methanol as the solvent hexyl bromide was converted to hexyl cyanide m 71% yield by heating with sodium cyanide Although this IS a perfectly acceptable synthetic reaction a peiiod of ovei 20 hours was lequued Changing the solvent to dimethyl sulfoxide brought about an increase m the reaction rate... [Pg.347]

Many synthetic reactions involving phenols as nucleophiles are carried out m the presence of sodium or potassium hydroxide Under these conditions the phenol is con verted to the corresponding phenoxide ion which is a far better nucleophile... [Pg.998]

Fig. 6. DNA sequence analysis, (a) Simplified methodology for dideoxy sequencing. A primer, 5 -TCTA, hybridized to the template, is used to initiate synthesis by DNA polymerase, (b) Stmcture of 2, 3 -dideoxy CTP. When no 3 -OH functionaUty is available to support addition of another nucleotide to the growing chain, synthesis terminates once this residue is incorporated into the synthetic reaction, (c) Representation of a DNA sequencing gel and the sequence, read from bottom to the top of the gel, gives sequence information in the conventional 5 to 3 direction. Fig. 6. DNA sequence analysis, (a) Simplified methodology for dideoxy sequencing. A primer, 5 -TCTA, hybridized to the template, is used to initiate synthesis by DNA polymerase, (b) Stmcture of 2, 3 -dideoxy CTP. When no 3 -OH functionaUty is available to support addition of another nucleotide to the growing chain, synthesis terminates once this residue is incorporated into the synthetic reaction, (c) Representation of a DNA sequencing gel and the sequence, read from bottom to the top of the gel, gives sequence information in the conventional 5 to 3 direction.

See other pages where Synthetic reactions is mentioned: [Pg.256]    [Pg.382]    [Pg.519]    [Pg.311]    [Pg.4]    [Pg.53]    [Pg.85]    [Pg.92]    [Pg.95]    [Pg.140]    [Pg.148]    [Pg.193]    [Pg.210]    [Pg.215]    [Pg.292]    [Pg.296]    [Pg.320]    [Pg.370]    [Pg.79]    [Pg.79]    [Pg.81]    [Pg.83]    [Pg.85]    [Pg.87]    [Pg.87]    [Pg.89]    [Pg.91]    [Pg.93]    [Pg.95]    [Pg.204]    [Pg.293]    [Pg.300]   
See also in sourсe #XX -- [ Pg.489 ]




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1.3- Dipolar cycloaddition reactions synthetic equivalents

Aldol reaction synthetic utility

Aldol reactions, synthetic applications

Alkyl halides synthetic reactions with

Allylation reactions synthetic applications

Allylic Halogenation Synthetically Useful Reactions

Amides, synthetic reactions

Applications of Cyclometalation Reactions and Five-Membered Ring Products for Synthetic Purposes

Cocatalysis catalysis of synthetic reactions

Complex Reactions and Synthetic Applications

Cross-coupling reactions synthetic applications

Crossed aldol reactions synthetically useful

Cycloaddition reactions synthetic routes

Deoxygenation reactions synthetic utility

Diels-Alder reaction synthetic applications

Diels-Alder reaction synthetic equivalents

Diels-Alder reaction synthetic utility

Diels-Alder reaction, synthetic methods

Domino and Intramolecular Rearrangement Reactions as Advanced Synthetic Methods in Glycoscience

Dyes, reactions synthetic

Electrode reactions synthetic techniques

Electron tunneling in reactions involving chlorophyll and its synthetic analogues

Elimination/addition reactions synthetic strategies

Enantioselectivity synthetic reactions

Enzymatic synthetic reactions

Features of Hydro(solvo)thermal Synthetic Reactions

General Synthetic Reactions

Green Synthetic Reactions

Haloform reaction synthetic utility

Henry reaction synthetic utility

Hiyama reaction synthetic applications

Intramolecular Heck Reaction on the Synthetic Route to Baccatin III

Knoevenagel reaction synthetic alternatives

Knoevenagel reaction synthetic applications

Knoevenagel reaction synthetic utility

Kumada reactions synthetic application

Mannich reaction synthetic utility

Mitsunobu reaction synthetic utility

Mizoroki-Heck reaction synthetic application

Modern Synthetic Reactions

Mukaiyama aldol reaction synthetic utility

Named Reaction SYNTHETIC BUILDING BLOCKS

Negishi cross-coupling reactions synthetic utility

Nickel-catalyzed reactions synthetic applications

Nitrile Converting Enzymes Involved in Natural and Synthetic Cascade Reactions

Organic Reaction vs. Synthetic Method

Organic Synthetic Reactions

Organic chemical reactions synthetically important

Organolithium synthetic reaction

Other Synthetic Reactions

Oxidation reactions synthetic utility

Pauson-Khand reaction synthetic utility

Photoaddition Reactions in Synthetic Organic Chemistry

Photochemical Cleavage Reactions in Synthetic Organic Chemistry

Photochemical Rearrangement Reactions in Synthetic Organic Chemistry

Photochemical Substitution Reactions in Synthetic Organic Chemistry

Polymerase chain reaction-synthetic

Polymerization reactions for synthetic polymers

Reaction center, synthetic

Reaction complexes, synthetic

Reaction databases general synthetic reactions

Reactions and Derived Synthetic Applications of Alkylidynetricobalt Nonacarbonyl Complexes

Reactions and Synthetic Applications

Reactions phase-transfer synthetic

Rearrangements—Synthetic Reactions Not Liable to Retrosynthetic Analysis

Reduction reactions synthetic utility

Retrosynthesis and Stereochemical Aspects of Synthetic Reactions

Ring closure reactions, synthetic strategy

Ritter reaction synthetic utility

Schmidt reactions synthetic utility

Sequential Synthetic Reactions of Metal-containing Allylic Silanes

Some Examples and Synthetic Applications of Type Cleavage Reactions

Some Synthetically Useful Carbonium-Ion Reactions

Some synthetically important nucleophilic substitution reactions

Sonogashira coupling reaction synthetic utility

Sonogashira reaction synthetic applications

Sonogashira reaction synthetic utility

Staudinger reaction synthetic utility

Stille reaction synthetic application

Suzuki reaction synthetic utility

Suzuki-Miyaura reaction synthetic application

Synthetic Applications of Chelated Ligand Reactions

Synthetic Applications of Deamination Reactions

Synthetic Benefits of the Petasis Borono-Mannich Reaction

Synthetic Methods 1 Cyclocondensation Reactions

Synthetic Models for Bioorganometallic Reaction Centers

Synthetic Reactions Based on the Chelation of Heteroatoms

Synthetic Reactions We Can Do So Far

Synthetic Reactions via Transition Metal Carbene Complexes

Synthetic Reactions with Organozinc Compounds

Synthetic Uses of Phosphine-Halogenocarbon Reactions

Synthetic Utilization of the Double Bond Cleavage Reactions

Synthetic antenna reaction center

Synthetic application of Diels-Alder reaction

Synthetic applications of the aqueous aza Diels-Alder reaction involving simple protonated iminium ions

Synthetic applications of the aqueous aza Diels-Alder reaction with protonated C-acyl iminium ions

Synthetic applications of the asymmetric aqueous aza Diels-Alder reaction with simple protonated iminium ions

Synthetic intramolecular Mannich reaction

Synthetic methods aldol type reactions

Synthetic multicomponent reactions

Synthetic polymers reactions

Synthetic processes reactions

Synthetic reaction parameters

Synthetic reaction scheme

Synthetic reactions nucleophilic substitution

Synthetic reactions with alkyl

Synthetically Useful Hydrogenolysis Reactions

Synthetically important reactions

Synthetically useful radical substitution reaction

Tandem reactions organolithium synthetic intermediates

Tandem reactions synthetic strategies

Tertiary synthetic reactions

Tetrahedral mechanism synthetic reactions

The synthetic reaction

Topics on Specific Synthetic Applications of Phosgenation Reactions

Wittig reaction synthetic utility

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