Ketones properties/recovery

The ketone hydrosilylation shown in Fig. 7 was used as a test reaction. This can be catalyzed by the fluorous rhodium complexes 16-Rf6 and 16-Rfs under fluorous/organic liquid/liquid biphase conditions [55,56]. These red-orange compounds have very httle or no solubihty in organic solvents at room temperature [57]. However, their solubilities increase markedly with temperature. Several features render this catalyst system a particularly challenging test for recovery via precipitation. First, a variety of rest states are possible (e.g., various Rh(H)(SiR3) or Rh(OR )(SiR3) species), each with unique solubility properties. Second, the first cycle exhibits an induction period, indicating some fundamental alteration of the catalyst precursor. 

Isopropyl ocetote is a wofer-whife pleosont-odored liquid with properties intermediote between ethyl and butyl acetates. It is miscible with most of the common organic solvents such os alcohols, ketones, esters, oils, hydrocarbons, etc., and it is a solvent for nitrocellulose, cellulose ocetate (of low viscosity) and a wide ronge of oils, fats, waxes, gums ond notural and synthetic resins. Like n-propyl ocetote, its solvent power for cellulose esters is increosed when lower aliphatic alcohols are added. It is largely used in the lacquer industry where its slow evaporation rate and blush resistance ore of importance. It is also used in the monufacture of plastics, artificial leather, dopes, films, cements, and in the recovery of acetic ocid from aqueous solutions. 

The environmental implications and human toxicities associated with halogenated compounds create the need for PHA solvents with more benign properties. In 1999 Monsanto was issued a patent for PHA recovery using a solvent which is a lower ketone, dialkyl ether or a lower alcohol or ester (75). It is preferred that oil be extracted from the vegetable matter before PHA... 

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