5-Phenylpentanoic acid

The complex [PtCl2(DIOP)] in the presence of SnCl2 has been used as catalyst for the asymmetric hydroformylation of various alkenes. With a series of butene and styrene derivatives very low optical yields were obtained. The best results were achieved with 2,3-dimethyl-l-butene which gave 15% optically pure 3,4-dimethylpentanal, and with a-ethylstyrene which gave 15% optically pure 3-phenylpentanoic acid after oxidation of the aldehyde.373... 

IUPAC name 4-aminobutanoic acid 3-phenylpentanoic acid 3-methylbutanoic acid... 

Hydrolyses of 3-methyl-3-phenylpentanenitri]e and 3-ethyl-3-methylhexanenitrile (cf. Note 11) by the described procedure gave 88% and 95% yields of 3-methyl-3-phenylpentanoic acid (b.p. 190-194°/26 mm., Mp 1.5182) and 3-etliyl-3 methyl hexa-noic acid (b.p. 136 137°/15 mm., 1.4377), respectively. 

The acid-catalyzed hydrolysis of butanamide proceeds as expected to give butanoic acid, 7. An example is the acid-catalyzed hydrolysis of the tertiary amide iV,iV-diethyl-3-phenylpentanamide (34) to give 3-phenylpentanoic acid (35). The initial product is iV,AT-diethylamine, but under the acid-catalyzed conditions, the basic amine reacts to form the observed product, ammonium salt, 36. Secondary and primary amides react in an identical manner the leaving group is an amine for the secondary amide, but it is ammonia for the primary amide. Acid hydrolysis of pentanamide, for example, gives pentanoic acid and ammonia (NHg) and, under acid conditions, the ammonia is converted to the ammonium ion (NH4+). When amides are heated with aqueous hydroxide, the products are the salt of the carboxylic acid and the amine. Acid hydrolysis of the carboxylate salt generates the acid, as with saponification. 

Acetyl-5-phenyl-2-pyrrolidone, A 30.5 3-Cyano-3-phenylpentanoic acid, A 39.12... 

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