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And propargyl compounds

Synthesis of y-lactones using tungsten alkynyl and propargyl compounds 98PAC1111. [Pg.251]

Palladium-Catalyzed Hydrogenolysis of Allylic and Propargylic Compounds with Various Hydrides. Tsuji, J. Mandai, T. Synthesis 1996,1. [Pg.417]

The medium influence on the solvolyses of a variety of further substrates, i.e. benzylic [310-313], allylic and propargylic compounds [312], as well as very crowded tertiary haloalkanes [314], has been studied and analyzed in the framework of the extended Grunwald-Winstein equation (7-15). [Pg.408]

Heterolytic cleavage of the tin-carbon bond is reviewed in references (94-96). Cleavage by electrophiles (e.g., HgXj or halogen) is dominated by electrophilic attack at carbon, and cleavage by nucleophiles principally involves nucleophilic attack at tin. Much of the interest in these processes centers on the intermediate mechanisms that may exist between these extremes, in which electrophilic attack is accompanied by some nucleophilic assistance, and vice versa. Allylic, al-lenic, and propargylic compounds show a special reactivity by a special (Se2 or Se2v) mechanism. [Pg.10]

In allylic and propargylic compounds the 8, 2 reaction in addition to undergoing nucleophilic substitution takes place with a rearrangement of a double bond (Fig. 3). [Pg.455]

Allylations, allenylations, and propargylations compounds in aqueous media can also be carried out with preformed organic tin reagent, rather than the use of metals.For example, the allylation reaction of a wide variety of carbonyl compounds with tetraal-lyltin was successfully carried out in aqueous media by using scandium trifluoromethanesulfonate (scandium inflate) as a catalyst (Eq. 8.40). A phase-transfer catalyst (PTC) was found to help the allylation mediated by tin at room temperature without any other assistance. ... [Pg.212]

A brief overview of the well-established chemistry of Pd-catalyzed carbon-carbon bondforming reactions involving allylic and propargylic compounds is presented. [Pg.40]

Palladium-catalyzed carbonylation of allylic and propargylic compounds offers a potential tool of one-carbon homologation. Particularly, pd-catalyzed carbonylation of propargylic compounds further provides synthetically valuable transformations because of the high reactivity of the intermediary allenyl esters. [Pg.862]

Hydrogenolysis of Allylic and Propargylic Compounds with Various Hydrides. [Pg.1488]

J. Tsuji and J. Kiji, in Transition Metals for Organic Synthesis, Vol. 1, M. Beller and C. Bolm, Eds., Wiley-VCH, Weinheim, 1998, 68-78. Palladium-Catalyzed Carbonylation of Allylic and Propargylic Compounds. [Pg.1492]

Reactions of Propargylic Compounds Catalyzed by Pd(Q) 5.2 Reactions with Alkenes and Terminal Alkynes... [Pg.455]

Acetylene is condensed with carbonyl compounds to give a wide variety of products, some of which are the substrates for the preparation of families of derivatives. The most commercially significant reaction is the condensation of acetylene with formaldehyde. The reaction does not proceed well with base catalysis which works well with other carbonyl compounds and it was discovered by Reppe (33) that acetylene under pressure (304 kPa (3 atm), or above) reacts smoothly with formaldehyde at 100°C in the presence of a copper acetyUde complex catalyst. The reaction can be controlled to give either propargyl alcohol or butynediol (see Acetylene-DERIVED chemicals). 2-Butyne-l,4-diol, its hydroxyethyl ethers, and propargyl alcohol are used as corrosion inhibitors. 2,3-Dibromo-2-butene-l,4-diol is used as a flame retardant in polyurethane and other polymer systems (see Bromine compounds Elame retardants). [Pg.393]

Copper(I) halide-catalyzed coupling reactions of perfluoro Gngnard reagents with allyl and propargyl halides have been reported [256], The acetylenic copper compound may be an intermediate in these reactions. [Pg.713]

A general method for the synthesis of highly substituted styrenes as 6/4-91, vinyl-cyclohexadienes and related compounds was developed by Xi, Takahashi and coworkers [301] by reacting an intermediately formed five-membered zirconacycle 6/4-89 with propargyl derivatives 6/4-90 or allyl bishalides in the presence of CuCl (Scheme 6/4.21). [Pg.470]

Organogermanium compounds can be prepared by transmetallation reactions with tin reagents. Examples include Me2PhGeCl (Equation (66)),89 the alkene-functionalized species 26-28, (Equations (67) and (68)),90 and the allenic (Equation (69)) and propargylic (Equation (70)) species 29 and 30.91 A series of aryltrichlorogermanes was prepared from the corresponding tin reagents (Equation (71), Table 9).92 Transmetallation with zirconium species can also be used (Equation (72), Table 10).93... [Pg.717]


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See also in sourсe #XX -- [ Pg.423 ]




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Allylation and Propargylation of Carbonyl Compounds

Hydrogenolysis and Elimination of Propargyl Compounds

Organometallic compounds allyl and propargyl/allenic

Propargyl compounds

Propargylation of Heteroaromatic and Aromatic Compounds with Propargylic Alcohols

Propargylic compounds

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