Reactions and Applications in Organic Synthesis

Trimesitylaluminium, as a thf solvate, is readily obtained by treating AlCl with either mesitylmagnesium bromide or dimesitylmagnesium in thf. Unsolvated material is produced by recrystallation from toluene. Reaction with mesityllithium yields lithium tetramesitylaluminate, whilst redistribution with AlCl  

The nature of organoaluminium compounds present in the A1C12-A1-C2H system has been examined. Under comparatively mild conditions (100-110°, 1 bar ethylene), both 1,1- and 1,2-ethanediylbis(dichloroaluminium) appear to be present, which give 

Although both compounds reduce TiCl., the 1,1-ethanediyl causes almost quantitative reduction to but eliminates 

Superficially innocuous changes in the amount of excess reagent used to prepare the alkynylalanes can lead to great changes in the resulting regioselectivity, even to the extent of reversing the isomer ratios. Substitution of an alanate for the usual alane 

The type of reaction observed is dependent upon the aluminium reagent employed. While the selective formation of secondary alcohols was observed in the reacation with i-Bu Al, the use of EtjAl led to the formation of a mixture of a ketone and two alcoholic products. With Et2AlCl predominantly unsymmetrical 

Irradiation by visible light Is understandable since It has been demonstrated tliat the Al-C bond of Al(TPP (Bt Is homoljrtlcally cleaved upon Irradiation by visible light In benzene In the presence of an excess of 2.4.6-trl-t-butylnltronltrosobenzene, yielding spin adducts of A1(TPP and ethylradlcals with a quantum yield of the order of 10. The Insertion of sulphur dioxide 

Into the gallium-carbon bond of galllum(IIl porph]rrlns CGa(Por R] gives rise to sulphlnato gallium porphyrins which are easily oxidised to the corresponding sulphonato coi plexes.  

Vestln, U. Vestln and J. Kowaleskl, Acta Chem. Scand.. 

Naruse, J. Ukal, V. Ikeda and H. Yamamoto, Cham. Letters. 

Salgado-Zamora and A. XcKlllop, Salgado-Zamora and A. XcKlllop, 

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Ring-Closing Metathesis (RCM) Reactions and Applications in Organic Synthesis... 

Both allyl- and cyclopentadienyl-stannanes will undergo SH2 (SH2-y) reactions to generate a stannyl radical.42-43 The intermediate adduct radical is stabilised by the presence of the p-stannyl substituent (see below). These reactions find application in organic synthesis and are discussed in Section 9.1.3.3. 

Deprez NR, Sanford MS (2007) Reactions of hypervalent iodine reagents with palladium mechanisms and applications in organic synthesis. Inorg Chem 46 1924—1935... 

R. A. Batey in Boronic acids preparation and applications in organic synthesis and medicine (D. Hall, Ed.). Wiley-VCH Verlag GmhH, Weinheim, Germany, 2005, pp. 279-304. NucleophUic addition reactions of aryl and alkenylboronic acids and their derivatives to imines and iminium ions. 

Z. G. Hajos, Aldol and Related Reactions , Carbon-Carbon Bond Formation (Techniques and Applications in Organic Synthesis Series, Vol. 1, ed. R. L. Augustine), Marcel Dekker, New York, 1979. 

The main goal of this chapter is to give a brief overview of reactions that have been catalyzed by cyclopentadienylmetal complexes and to show their potential and application in organic synthesis. The reactions have been classified into seven types according to their similar features. The tables give some representative examples of chemical transformations. In some cases presumed reaction mechanisms are also shown for better understanding of the course of the reaction. It is necessary to emphasize that the list of the reactions and possible applications is by no means final and many new interesting applications and reactions can be expected to appear in the near future. 

Trimethylsilyl trifluoromethanesulfonate (trimethylsilyl triflate) is the most synthetically useful representative of the family of trialkylsilyl perfluoroalkane-sulfonates (for a review, see reference 101) This reagent is commercially available or can be prepared easily by the reaction of chlorotrimethylsilane and triflic acid [101] It has wide application in organic synthesis as an excellent silylating reagent... 

The nitro-dldolredcdon between nitrodlkdnes and carbonyl compounds to yieldfi-nitro alcohols was discovered in 1895 by Henry. Since dien, diis reaction has been used extensively in many important syndieses. In view of its significance, diere are several reviews on die Henry reaction." These reviews cover syndiesis of fi-nitro alcohols and dieir applications in organic synthesis. The most comprehensive review is Ref 3, which summarizes the literature before 1970. More recent reviews are Refs. 4 and 5, which summarize literatures on the Henry reaction published until 1990. 

Arylmetallic compounds have various, but not very widely used, applications in organic synthesis. Examples are acyl-de-metallation reactions using either dicobalt octacarbonyl in tetrahydrofuran (Seyferth and Spohn, 1969 Scheme 10-92), or carbon monoxide and a rhodium catalyst (Larock and Hershberger, 1980). 

Abstract For many years after its discovery, olefin metathesis was hardly used as a synthetic tool. This situation changed when well-defined and stable carbene complexes of molybdenum and ruthenium were discovered as efficient precatalysts in the early 1990s. In particular, the high activity and selectivity in ring-closure reactions stimulated further research in this area and led to numerous applications in organic synthesis. Today, olefin metathesis is one of the... 

Dihydro-1-vinylnaphthalene (67) as well as 3,4-dihydro-2-vinylnaphtha-lene (68) are more reactive than the corresponding aromatic dienes. Therefore they may also undergo cycloaddition reactions with low reactive dienophiles, thus showing a wider range of applications in organic synthesis. The cycloadditions of dienes 67 and 68 and of the 6-methoxy-2,4-dihydro-1-vinylnaphthalene 69 have been used extensively in the synthesis of steroids, heterocyclic compounds and polycyclic aromatic compounds. Some of the reactions of dienes 67-69 are summarized in Schemes 2.24, 2.25 and 2.26. In order to synthesize indeno[c]phenanthrenones, the cycloaddition of diene 67 with 3-bromoindan-l-one, which is a precursor of inden-l-one, was studied. Bromoindanone was prepared by treating commercially available indanone with NBS [64]. 

The first chapter presents the general aspects of the reaction Chapters 2-6 illustrate the various methods and their applications in organic synthesis. At the end of each chapter a list of graphically abstracted Diels-Alder reactions is presented to show selected synthetic applications of the specific methodology. The discussion of the various topics is not exhaustive because our aim has been to emphasize the synthetic potential of each method. Chapter 7 reports a list of books, reviews, monographs and symposia proceedings which have appeared since 1990 and an index of keywords to help the reader find a particular paper of interest. 

Cyanocuprates constitute a class of organocopper compounds that finds applications in organic synthesis.234 They are prepared by the direct reaction of an organolithium reagent and CuCN, with two different types of compounds being prepared depending on the stoichiometry employed the 1 1 ratio leads to RCu(CN)Li compounds whereas the 2 1 mixture affords R2Gu(GN)Li2. The lower- order or 1 1 cyanocuprates usually display the Cu-C-N-Li... 

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