Cis- 2- PHENYLCYCLOPROPANECARBOXYLIC ACID

B. cis-2-Phenylcyclopropanecarboxylic acid. In a 1-1. threenecked flask equipped with a dropping funnel, stirrer, and a... 

Burger and Yost4 reported m.p. 106-107° for pure cis-2-phenylcyclopropanecarboxylic acid and m.p. 93° for pure [Pg.97]

The present method offers a convenient preparation of cis-2-phenylcyclopropanecarboxylic acid that is amenable to large-scale work. The process above has been carried out in the laboratories of the submitters on a twentyfold scale with essentially the same results. The method also provides an example of the separation of two isomers based on differences in reaction rate. 

Since (Z)- and ( )-stereoisomers of unsaturated oxazolones can be obtained using appropriate isomerization procedures, cis and trans isomers of cyclopropane derivatives can be obtained in a stereoselective manner, although special care must be taken with experimental conditions to obtain the best stereoselectivity. Both racemic cis- and fraui-l-amino-2-phenylcyclopropanecarboxylic acid 641 and 644 have been obtained from the corresponding (Z)- or ( )-4-benzylidene-2-phenyl-5(4//)-oxazolone 621 and 642 using diazomethane. Care was taken to affect the... 

A solution of the above ester (207.8 grams) and 64.5 grams of sodium hydroxide in 80 cc of water and 600 cc of ethanol is refluxed for 9 hours. The carboxylic acid of 2-phenylcyclopropane is liberated with 200 cc of concentrated hydrochloric acid. The 2-phenylcyclopropanecarboxylic acid contains 3 to 4 parts of the trans isomer to 1 part of the cis isomer. The acid is recrystallized from hot water. The pure trans isomer comes out as crystalline material (solid) while the cis isomer stays in solution. 

Oxidative decarboxylation of cis- and tra .v-2-phenylcyclopropanecarboxylic acid (19) by lead tetraacetate in anhydrous benzene containing copper(II) acetate and pyridine as catalyst affords a mixture of 7 products in a total yield of 55-58% among which phenylcyclopropane (20) and, 2-diphenylcyclopropane (21) were present in only 1.2% and 15% yield, respect-... 

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