P-Chlorobenzhydryl chloride

Hydroxyethyl)piperazine p-Chlorobenzhydryl chloride Diethylene glycol... 

A mixture of 1.5 mols of 1-(2 -hydroxyethyl)piperazine and 1 mol of p-chlorobenzhydryl chloride is heated at 150°C for 15 minutes. The substance is dissolved in water, basified by caustic soda and extracted with benzene. 

We have previously discussed the possibilities of racemization or inversion of the product RS of a solvolysis reaction. However, the formation of an ion pair followed by internal return can also affect the stereochemistry of the substrate molecule RX. Cases have been found where internal return racemizes an original optically active RX, an example being solvolysis in aqueous acetone of a-p-anisylethyl p-nitrobenzoate, while in other cases partial or complete retention is found, for example, solvolysis in aqueous acetone of p-chloro benzhydryl p-nitrobenzoate. the pathway RX R+X some cases where internal return involves racemization, it has been shown that such racemization is faster than solvolysis. For example, optically active p-chlorobenzhydryl chloride racemizes 30 times faster than it solvolyzes in acetic acid. ... 

Bowden and Thomas report that the effect of methyl groups on the conductivity of trityl chloride in sulfur dioxide is in the order p>o>m> none.1 1 The trityl chloride-stannic chloride complex and a whole series of trityl bromides are strong electrolytes in sulfur dioxide.160-152 Benzhydryl chloride, ra-chlorobenzhydryl chloride, and -dimethylbenzhydryl chloride do not conduct in sulfur dioxide. Earlier reports to the contrary may have been due to the use of impure compounds.162 Dimesitylmethyl chloride has also been reported to conduct in sulfur dioxide.163... 

Lui et al. [8] prepared buclizine by reducing p-chlorophenyl phenyl ketone 1 with potassium borohydride to p-chlorobenzhydryl alcohol 2, which was converted into p-chlorobenzhydryl bromide 3. The latter compound 3 was prepared by reaction of p-chlorophenylmagnesium bromide 4 with benzaldehyde 5. p-ferf-Butylbenzyl chloride 6 was condensed directly with piperazine 7 to give p-ferf-butylbenzylpiperazine 8. Treatment of p-chlorobenzhydryl bromide 3 with p-ferf-butylbenzylpiperazine 8 in the presence of anhydrous sodium carbonate gave buclizine 9 hydrochloride. 

Cossement et al. [9] s)nithesized the enantiomers of l-(p-chlorobenzhy-diyl)-4-(p-methylphenyl)sulfonyl piperazine 3 and used it as an intermediate for fhe preparation of buclizine 6 and other histamines. The enantiomers of (+)- and (—)-l-(p-chlorobenzhydryl)-4-(p-foluene sulfo-nyl)piperazine 3 were prepared and converted by hydrolysis to the enantiomers of (+)- or (—)- of p-chlorobenzhydryl piperazine 4. Compound 3 was prepared by refluxing p-chlorobenzhydrylamine 1 with N-bis-2-chloroethyl-p-toluene sulfonamide 2 with ethyl diisopropylamine. Reaction of p-ferf-bufylbenzyl chloride 5 wifh p-chlorobenzhydryl piperazine 4 gives buclizine 6. 

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