Cyclopentanone alkanal

On photolysing cyclobutanone and cyclopentanone in the presence of excess ethylene. Flowers and Frey reported the formation of long-chain aliphatic and cyclic alkanes, considering it as a confirmation of the biradical mechanism. However on repeating these experiments,other workers did not observe the formation of the products reported by Flow.r and Frey, not even in the presence of 1 atm of C2H4. 

Tables 3-1 through 3-3 contain data on which empirical calculations of chemical shifts can be made. The tables represent a fraction of the data available on the fundamental alkane, alkene, and aromatic structures. Moreover, corrections must be applied in order to avoid nonadditivity caused primarily by steric effects. Thus, three groups on a single carbon atom, two large groups cis to each other on a double bond, or any two ortho groups can cause deviations from the parameters listed in the tables. If sufficient model compounds are available, the corrections shown can be applied. Further empirical calculations are possible for any structural entity, so that the eclipsing strain in cyclobutanes, the variety of steric interactions in cyclopentanones, or the variations in angle strain in norbornanes may be taken into account.

Fig. 6 Chromatograms of extractions from virgin and recycled polyamide 6.6 after 25 h of thermo-oxidation at 100 °C. Identity of the peaks is 1 = cyclopentanone, 2 = 2-methylpyridine, 3 = pentanoic acid, 4 = butanamide, 5 = 2-ethylcyclopentanone, 6 = 2,4,6-trimethylpyridine, 7 = pentanamide, 8 = 3-(l-methylethyl)pyridine, 9 = 2-butylpyridine, 10 = N,N-hexamethylenebisformamide, 11 = 2-butylcyclopentanone, 12 = glutarimide, 13 = l-propyl-2,5-pyrrolidinedione, 14 = 2-pentylcyclopentanone, 15 = caprolactam, 16 = azepane-2,7-dione, 17 = 2-cyclopentyl-cyclopentanone, 18= l-butyl-2,5-pyrrolidinedione, 19 = l-pentyl-2,5-pyrrolidinedione, 20 = 2-butyl-3,5-dimethylethylpyridine, L1-L7 = linear C13-C17 alkanes and alkenes from lubricant, = silicone from septa used to seal vials. Reprinted from [65] with permission of John WUey Sons, Inc. John Wiley Sons, Inc (2002)...

Synthesis of spirocyclic ketones can be achieved by the thermal reaction of cyclic ketones with a,co-dibromoalkanes in the presence of a base [189, 190]. However, these conditions simply promote rapid self-condensation in the case of cyclopentanone [189] restricting the general applicability of the method. In contrast, sonolysis of the reaction mixture gives good yields of spiro-(4,n)-alkan-l-ones [191] (Scheme 86). 

Marongiu, B. Dernini, S. Polcaro, A. M. Thermodynamics of binary mixtures containing cyclic alkanones. Excess enthalpies of cyclopentanone and cyclohexanone + n-alkanes, + cyclohexane, + benzene, and + tetrachloromethane J. Chem. Eng. Data 1986, 31,185-189... 

Data from Norman Jones group at the National Research Council of Canada were used for two figures on cyclopentanone spectra in Chapter 1, for several of the spectra of alkanes in Chapter 2, and for the band patterns of substituted benzenes in Chapter 5. In Chapter 5 the combination band patterns for pyridine systems were derived from the work of Katritsky at Cambridge University. 

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