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P acyclic

StaR73 Stanley, R. P. Acyclic orientations of graphs. Discrete Math. 5 (1973) 171-178. [Pg.147]

Let C be a P°°-acyclic (n+1)-dimensional A-roodule chain complex, so that is an Sp-acyclic (n+l)-dimensional... [Pg.401]

Gree, R. Lellouche, J. P. Acyclic Diene Tricarbonyliron Complexes in Organic Synthesis. Advances in Metal-Organic Chemistry. Vol. 4. Liebeskind, L. S., Ed. JAI Greenwich, Connecticut,... [Pg.8]

An acyclic monterpene, b.p. 166-168°C, found in many essential oils, e.g. in verbena oil and oil of hops. [Pg.268]

The stereochemistry of radical addition of hydrogen bromide to alkenes has been studied with both acyclic and cyclic alkenes. Anti addition is favored.This is contrary to what would be expected if the s[p- carbon of the radical were rapidly rotating or inverting with respect to the remainder of the molecule ... [Pg.709]

When this type of transform is applied mechanistically to 85, retron generation is simple, for example by the change 85 => 86, and the sequence 86 => 90 disconnects two rings and provides an interesting synthetic pathway. Radical intermediate 88, which is disconnected at p-CC bond a to produce 89, may alternatively be disconnected at the P-CC bond b which leads to a different, but no less interesting, pathway via 91 to the acyclic precursor 92. The analysis in Chart 11 is intended to illustrate the mechanistic transform method and its utility it is not meant to be exhaustive or complete. [Pg.29]

Perfluoroallyl fluorosulfate is prepared by the treatment oiperfluoropropene with sulfur tnoxide m the presence of boron catalysts [2, 3, 4, 5, 6, 7] (equation 2) Perfluoroisopropyl allyl ether reacts similarly to give 58% polyfluoroallyl fluorosulfate in a cis/trans ratio of 6 4 [S] Sultones are the exclusive products without catalyst. Polyfluoroolefins such as 2-hydropentafluoropropylene [9], (2,3-dichloropropyl)tri-fluoroethylene [70], perfluoropropene [2, i], perfluoroisopropyl alkenyl ethers [S], and acyclic polyfluoroallyl ethers [77] undergo sulfur trioxidation to regioselectively produce the corresponding P-sultones in high yield... [Pg.403]

It is a yellow solid with an acyclic structure (Fig. 15.49a), cf N2O5 (p. 458). Moist air converts S3N2O2 to SO2 and S4N4 whereas SO3... [Pg.740]

A chance observation made some time prior to the full structural elucidation of cocaine in fact led to one of the more important lasses of local anesthetics. It was found that the simple ethyl e. ter of p-aminobenzoic acid, benzocaine (25), showed activity. 1-. a local anesthetic. It is of interest to note that this drug, I 1rst introduced in 1903, is still in use today. Once the struc-iiire of cocaine was established, the presence of an alkanolamine iiiniety in cocaine prompted medicinal chemists to prepare esters "I aminobenzoic acids with acyclic alkanolamines. Formula 26 11 presents the putative relationship of the target substances with cocaine. [Pg.9]

Until this work, the reactions between the benzyl sulfonium ylide and ketones to give trisubstituted epoxides had not previously been used in asymmetric sulfur ylide-mediated epoxidation. It was found that good selectivities were obtained with cyclic ketones (Entry 6), but lower diastereo- and enantioselectivities resulted with acyclic ketones (Entries 7 and 8), which still remain challenging substrates for sulfur ylide-mediated epoxidation. In addition they showed that aryl-vinyl epoxides could also be synthesized with the aid of a,P-unsaturated sulfonium salts lOa-b (Scheme 1.4). [Pg.5]

Kuokkanen evaluated a series of constants. Kpeg for substituted diazonium ions with PEG 1000 and found a reaction constant (p = 1.12) comparable to those for complexation with the three crown ethers investigated by Nakazumi et al. (1983), p = 1.18-1.38). It is therefore likely that the host-guest interaction of diazonium ions with acyclic polyethers is basically similar to that with crown ethers. A dual substituent parameter analysis (DSP, see Sec. 8.3) for (Nakazumi et al., 1987)... [Pg.298]

The oxidation of a series of cyclic and acyclic sulphides by cytochrome P 450from rabbit liver gave sulphoxides with / -configuration at sulphur. The maximum of the e.e. value (53.8%) was observed for benzyl t-butyl sulphoxide310. [Pg.293]

On the other hand, a very high asymmetric induction was observed in the 1,3-dipolar cycloaddition of (/ )-( + )-p-tolyI vinyl sulphoxide 578 with acyclic nitrones. The reaction... [Pg.360]

Olefin metathesis, an expression coined by Calderon in 1967,1 has been accurately described in Ivin and Mol s seminal text Olefin Metathesis and Metathesis Polymerization as the (apparent) interchange of carbon atoms between a pair of double bonds (ref. 2, p. 1). This remarkable conversion can be divided into three types of reactions, as illustrated in Fig. 8.1. These reactions have been used extensively in the synthesis of a broad range of both macromolecules and small molecules3 this chapter focuses on acyclic diene metathesis (ADMET) polymerization as a versatile route for the production of a wide range of functionalized polymers. [Pg.431]


See other pages where P acyclic is mentioned: [Pg.145]    [Pg.76]    [Pg.397]    [Pg.823]    [Pg.825]    [Pg.827]    [Pg.830]    [Pg.145]    [Pg.76]    [Pg.397]    [Pg.823]    [Pg.825]    [Pg.827]    [Pg.830]    [Pg.285]    [Pg.67]    [Pg.105]    [Pg.438]    [Pg.232]    [Pg.250]    [Pg.113]    [Pg.50]    [Pg.51]    [Pg.51]    [Pg.744]    [Pg.695]    [Pg.722]    [Pg.729]    [Pg.737]    [Pg.222]    [Pg.222]    [Pg.156]    [Pg.258]    [Pg.178]    [Pg.180]    [Pg.219]    [Pg.134]    [Pg.96]    [Pg.399]    [Pg.564]    [Pg.632]    [Pg.688]    [Pg.691]    [Pg.200]   
See also in sourсe #XX -- [ Pg.1001 ]




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