01efin

A -01efin formation can be avoided with thionyl chloride-pyridine by keeping the exposure brief and operating at low temperature in addition, the reagent may be used in the presence of a A" -3-ketone ... 

T-01efin-cobalt(III) complexes have not yet been observed directly, but have been postulated as intermediates in various reactions (see Section VI,B,l,d and the preceding section). 

There had been some evidence that alkoxide ligands slow down reactions which involve elimination of a p-hydride from an alkyl ligand. a-01efins are dimerized to a mixture of head-to-tail and tail-to-tail dimers by olefin complexes of the type Tafr -CsMes)-(CH2=CHR)Cl2 (10). The p,p1- and a,p -disubstituted tantalacyclo-pentane complexes are intermediates in this reaction. Their decomposition involves the sequence shown in equation 5. When one... 

A2-01efins in the 5a-series are frequently formed by elimination from the tosylates of 3/ -alcohols. Contamination with A3-compound is common, and purification via a derivative (e.g. dibromide) may be necessary (see page 343).86,227,228 A 2-methyl substituent increases the selectivity ... 

The alkyl lithium method gives high yields of A16-olefins from 17-ketones via the tosylhydrazones. A6-01efins are formed from 6- and 7-ketones.321 323 (Compare with the Bamford-Stevens reaction which gives A5- and A7-olefins, respectively.) In the presence of an excess of alkyl lithium, alkylation may occur.324... 

NF3-01efin Systems. Mixtures of NF3 with ethylene and 1,1-di-fluoroethylene (as well as acetylene) were irradiated to see if addition across the olefinic double bond might occur or whether N—F groups might be incorporated into the molecule by some other means. The... 

S,y-01efinic acids are readily converted to y-lactones by the action of boiling 50% sulfuric acid. branching on the y-carbon atom greatly increases the ease of lactonization. The same lactones ate obtained from the mote readily available a,/3-olefinic acids, which are isomerized and laptonized under the same conditions. 

Olefinic acetals, preparation, 263 preparations listed in table 23, 268 a, S-01efinic acetals, preparation, 37 Olefinic acetylenes, addition of alcohols, 233, 266 alkylation, SO partial reduction, 46 preparatioh, 34, 39, 46, 48, 80 preparations listed in table 6, 84 Olefinic acids, addition, of halogen, 107... 

C, 20 atm, 5V=3000 ml/g-cat./h, H2/C02=3. Results after 5 h. Molar ratio. Ratio, Si02/Al203, in the parentheses. Reference catalysts of the Catalysis Society of Japan. MeOH-nEtOH+PrOH. 01efin/(olefin+paraffin)/% of C2, C3 and C4. ranched/(branched+linear)/% of C4, C5, and C(,. 

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