Isopropyl phenyl ketone

The PennPhos ligands, for example 108, complexed with rhodium, provide an excellent system for the hydrogenation of aryl alkyl ketones with ee values in the range of 94-96% (Eq. 362). Phenyl isopropyl ketone shows only a 72% ee under similar conditions. Dialkyl ketones exhibit ee values in the range of 73-94% with this system (Eq. 363).640... 

AR86 C10H12O phenyl Isopropyl ketone c6h5coch(ch3)2 EtOH aq PO KOH 1 - - " -/- 0-2 -... 

When the vinyllithium intermediate (190) is treated with water, the procedure provides a useful synthetic method for the conversion of ketones to alkenes (Scheme 79). The method is illustrated by the conversions of the tosylhydrazones of phenyl isopropyl ketone (194) and dipropyl ketone (195) to the alkenes (196) and (197), respectively (Scheme 79). In this method, experiments have demonstrated that the hydrogen is derived from the water, as indicated in Scheme 79, and thatTMEDA is an excellent solvent. The vinyllithium intermediate (190) may be trapped by other electrophiles thus, with carbon dioxide and DMF, the reaction affords ,[i-unsaturated carboxylic acids and aldehydes like (198) and (199) (Scheme 80). 

Reaction of several bicyclo[2,2,l]heptenes with phenyl(trichloromethyl)mer-cury reveals the fact that born-2-ene (281) (the synthesis of which has just appeared in Organic Syntheses ) is completely unreactive to this substance, because steric hindrance prevents the cxo-attack required by torsional strain. The labelled bornyl-isobornyl Grignard mixture (282) undergoes cis-exo eliminative transfer to phenyl isopropyl ketone, although to a lesser extent than in the norbornyl system, this probably being a reflection of the fact that the gem-dimethyl group reduces the energy difference between exo- and e/ido-transfer. ... 

Carbonyl compounds include isobut3raldehyde, phenyl isopropyl ketone, glyoxylic acid and pyruvic acid. Diaryl ketones do not react. Modifications of the method consist in the use of a borohydride exchange-resin, of sodium triacetoxyborohydride NaBH(OAc)3 or in treating a mixture of a ketone and an amine with an equivalent of titanium(IV) chloride and Hiinig s base (ethyldiisopropylamine) in dichloromethane, followed by a methanolic solution of sodium cyanoborohydride. The borane-pridine complex and hydrogen telluride are excellent replacanents for sodium cyanoborohydride. 

The products may be isolated by fractional distillation but, on occasion, separation of the mixtures presents formidable difficulties, even by gas chromatography, and the relative proportions of the products can only be computed indirectly after having been subjected to further reactions. Phenyl isopropyl ketone yields the thiazolidine almost exclusively (55%). The observed cyclizations may be accounted for by several mechanisms, but the experimental evidence does not as yet allow of a final choice. Under the usual conditions, ethyleneimines and aldehydes yield merely adducts, viz. l-(hydroxyalkyl)aziridines (286), which fail to react with... 

Since the reaction of acetyl peroxide with phenyl isopropyl ketone at 115°C did give resinous material ( ) we must conclude that isomerization products of 6 could not have been involved in the formation of this material. 

The reaction of 2-methyl-2-phenylpropanal and GaCl3 gave a rearranged phenyl isopropyl ketone, in which phenyl migration proceeded to the carbonyl carbon as induced by GaCls (Scheme 7.25) [47]. Imidazolyl chloride was used as the acid... 

---