N-Propylmagnesium bromide

The yield obtained with n-propylmagnesium bromide depends upon the efficiency of separation from the reduction product, ethyl sec-butylcyanoacetate, b.p. 126°/22 mm., nff 1.4277/... 

The ester (3) has been shown to be a useful starting point for the synthesis of Elaeocarpus alkaloids. Ester (3) is converted by several steps into the protected keto-aldehyde (4) this, by reaction with n-propylmagnesium bromide followed by a Jones oxidation of the product and then deprotection, gives the diketone (5). As... 

The ether 8 has also been used to prepare n-propyldiphenylcyclopropenyl cation 9 as either the perchlorate or fluoroborate by reaction with n-propylmagnesium bromide and subsequent hydride abstraction of the resulting impure 3-n-propyldiphenylcyclopropene with triphenylmethyl cation (equation 5). 

The fluoroborate of 11 could be prepared from the perchlorate or directly from the cyclopropene 10. This ion was used to synthesize tri-n-propylcyclopropene (12), either by direct reaction with n-propyllithium or by conversion of the cation to di-n-propylcyclopropenyl methyl ether (13) and reaction of this compound with n-propylmagnesium bromide. The cyclopropene was converted directly to the ion 14 with triphenylmethyl perchlorate (equation 6). 

Some years later, stereoselective syntheses of a variety of optically active esters of arsinthious acids were reported. The esters were prepared by treating secondary chloroarsines with thiols in the presence of (—)-N,N-diethyl-a-methylbenzylamine. The n-pentyl ester 135, when allowed to react with n-propylmagnesium bromide, gave (R)-(—)-65 with low stereoselectivity and inversion at arsenic as indicated in equation 19 (Table... 

The reaction of 1 molEq of n-propylmagnesium bromide with 1 molEq of diisopropyl ketone, a sterically crowded ketone, gave the normal addition reaction product in only low yields the major product of the reaction was the reduction reaction product, formed by the transfer of a /-hydrogen from the Grignard reagent to the ketone. Owing to an enolization reaction (Scheme 21), 3% unreacted ketone could be isolated ... 

A comparison of the results of reactions of n-propylmagnesium bromide and isopropylmagnesium bromide with (substituted) benzophenones [15b] led the authors to some conclusions that are presented in Table 4. 

Hexamethylphosphoramide added to n-propylmagnesium bromide prepared from -propyl bromide in dry ether, the resulting soln. stirred vigorously under CO-pressure in an autoclave, then treated with 1 N HCl -> product. Y 56%. -a-Hydroxyketones from 2 halide molecules are obtained partially with sec. halides and exclusively with tert. ones. F. e. s. W. J. J. M. Sprangers, A. P. van Swieten, and R. Louw, Tetrah. Let. 1974, 3377. 

Cadmium chloride/n-propylmagnesium bromide CdClJn-C HjMgBr... 

Carboxylic acids. Vinylcyclohexane refluxed 18 hrs. with n-propylmagnesium bromide and some titanium tetrachloride, then treated with GO2, and hydrolyzed -cyclohexylpropionic acid. Y 51%. F. e., also preferential reaction, s. H. L. Finkbeiner and G. D. Cooper, J. Org. Chem. 26, 4779 (1961) 27, 1493, 3395 (1962). 

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