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Bicyclic compounds, and

Bekiaris et al. have studied the reaction of fluorinated pentane-2,4-diones and phosphanes and have reported the formation of bicyclic compounds and phosphaadamantanes <1997CB1547>. Compounds 167 and 168 were formed in a diasteroselective manner (Scheme 13) and their structures were determined by single crystal X-ray structure analysis. [Pg.547]

C-NMR chemical shifts of the heterocyclic rings of selected bicyclic compounds and of homoberbine-type isoquinobenzazepines (including the alkaloid saulatine, 11) are listed in Tables 9 and 10, respectively. Shifts of a-olefinic and (at higher field) )S-olefinic carbon atoms of enamines 77a, 288, and 292-294 and of the iminium group carbon atom in bicyclic salt 60 are found in the respective regions reported in the literature to be typical of such compounds (82T1975, p. 1986). [Pg.133]

Since most of the bicyclic compounds and their derivatives considered here are solids, they are commonly purified by recrystallization. Methanol and ethanol are frequently chosen as recrystallization solvent. [Pg.277]

A novel EtAlCl2-induced cyclization of 6-allylcyclohexenones (27) has been shown to provide bicyclic compounds and tricyclic compounds44 (not shown). [Pg.444]

Although it is not surprising that Wiberg extended to tricyclic systems (propellanes) his studies on hybridization of the bridgehead carbons in small-ring bicyclic compounds and the chemistry resulting therefrom, we shall perhaps extend somewhat the realm of the propellane substrates. This is done pragmatically (every definition is, by definition, arbitrary) in order to permit inclusion of certain piquant results. [Pg.1208]

We discussed bicyclic compounds and bridgehead double bonds in Chapter 19. [Pg.735]

NEA is N-ethylamphetamine, NM-X is the exo- and NM-N the endo-isomer of 2-methyl-aminobenzobicyclo[2.2.2]octene, and 2M-X is the exo- and 2M-N the endo-isomer of 2-methylaminobenzobicyclo[2.2.1]heptene. The numbering for Ct through C9 and N10 is as shown in Figure 13. Ctl is the carbon attached to the nitrogen (the N-methyl substituent in the bicyclic compounds and the methylene group of the ethyl substituent in NEA), C1X is the bridgehead atom of the bicyclic system that is not a part of the amphetamine skeleton, and C1S and Cn are the bridge atoms (not part of the amphetamine skeleton) bonded to atoms C7 and C12. [Pg.466]

Theoretical calculations show that the diradical form is usuaUy more stable than the equally possible /l -phosphane species seen at the far right of Fig. 5.19. Structures with a carbon carbon single bond forming a bicyclic compound and aromatic 6. -electron system involving both phosphorus lone pairs are predicted to be even less stable. [Pg.55]

The reaction has been the subject of reviews,316,45 from which it will be seen that the reaction can be applied to synthesis of five- and six-membered oxygen-heterocycles, sulfur-heterocycles, bicyclic compounds, and compounds containing an additional heteroatom in the ring. [Pg.1063]

We could form the enolate anion on the other side of the ketone at the orange site and attack the ester in the same way. The product would be a bridged bicyclic diketone, and is not formed (see above). The third possible enolate site (brown) could give an aldol reaction but the product would again be a bridged bicyclic compound and is not formed. [Pg.653]

We have just looked at the way the reactivity of an epoxide gains additional subtleties when it is fused into a bicyclic structure with a six-membered ring. We re now going to look more generally at bicyclic compounds and their reactivity, and consider some features of their stereoselective reactions. [Pg.839]

Chiraldex B-PH Structural isomers, unsaturated no aromatie eompounds. Linear and cyclic amines and alcohols, acids, lactones, amino aleohols, sugars, bicyclic compounds and epoxides. [Pg.445]

Alder, R. W. (1983). Medium-Ring Bicyclic Compounds and Intrabridgehead Chemistry. Accounts of Chemical Research, 16(9), 321-327. [Pg.52]

It could be expected that by using appropriate substrates free radical intramolecular addition could be used to synthesize bicyclic compounds and that the yields would be best in the CyS/Cy6 case. This is why we shall Hrst discuss examples involving the CyS/Cy6 case. [Pg.217]

Compounds that contain two fused rings are called bicyclic compounds, and they can be drawn in different ways ... [Pg.147]

This rule also appfies to bridged bicyclic compounds and is called Bredt s rule. Specifically, Bredt s rule states that it is not possible for a bridgehead carbon of a bicyclic system to possess a C=C double bond if it involves a trans it bond being incorporated in a small ring. For example, the following compound is too unstable to form ... [Pg.340]

An eight-membered ring is the smallest size ring that can accommodate a trans double bond. This rule also applies to bridged bicyclic compounds and is called Bredt s rule. [Pg.384]

Vol. 19. General subject index and group index Vol. 20. General formula index Series 1 and II (volumes 1-11) were never published. Volume 12 was issued in two parts, 12A Bicyclic compounds, and 12B Naphthalene, in nine volumes (1948-1955). Volume 13 was published in 1946 and volume 14 in 1940 to which six supplements were added 1951-1962. Supplements 5 and 6 were issued under the auspices of the Beilstein Institute who took over the encyclopaedia in 1954 and combined it with the current supplement to Beilstein. The system of arrangement of Elsevier depends on the structure of the compound and brings together those that are most closely related. Occurrence in nature and in technical products is discussed followed by syntheses from systems with fewer carbon atoms and formation by the degradation of more complicated systems. [Pg.149]


See other pages where Bicyclic compounds, and is mentioned: [Pg.278]    [Pg.95]    [Pg.70]    [Pg.214]    [Pg.41]    [Pg.43]    [Pg.37]    [Pg.311]    [Pg.147]    [Pg.793]    [Pg.236]    [Pg.66]    [Pg.326]    [Pg.387]    [Pg.411]    [Pg.405]    [Pg.520]    [Pg.359]    [Pg.202]    [Pg.295]   


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