Butyl chlorides, preparation

After the butyl chloride fraction has been collected, change the receiver and continue the distillation untU the zinc chloride commences to crystallise. Allow to cool and stopper the flask. The anhydrous zinc chloride thus obtained may be used in another preparation and recovered repeatedly. This results in considerable economy when the preparation is conducted by a large number of students. 

In a 250 ml. separatory funnel place 25 g. of anhydrous feri.-butyl alcohol (b.p. 82-83°, m.p. 25°) (1) and 85 ml. of concentrated hydrochloric acid (2) and shake the mixture from time to time during 20 minutes. After each shaking, loosen the stopper to relieve any internal pressure. Allow the mixture to stand for a few minutes until the layers have separated sharply draw off and discard the lower acid layer. Wash the halide with 20 ml. of 5 per cent, sodium bicarbonate solution and then with 20 ml. of water. Dry the preparation with 5 g. of anhydrous calcium chloride or anhydrous calcium, sulphate. Decant the dried liquid through a funnel supporting a fluted Alter paper or a small plug of cotton wool into a 100 ml. distilling flask, add 2-3 chips of porous porcelain, and distil. Collect the fraction boiling at 49-51°. The yield of feri.-butyl chloride is 28 g. 

Alternatively, use the equivalent amount of n-butyl chloride and prepare the Grignard reagent as for aec.-biltyl magnesium chloride. 

The reason for this is that reaction (i) is usually much slower than (ii) and (iii) so that the main reaction appears to be (Iv) (compare the preparation of tertiary butyl chloride from tertiary butyl alcohol and concentrated hydrochloric acid, Section 111,33). If the reaction is carried out in the presence of P3rridine, the latter combines with the hydrogen chloride as it is formed, thus preventing reactions (ii) and (iii), and a good yield of the ester is generally obtained. The differentiation between primary, secondary and tertiary alcohols with the aid of the Lucas reagent is described in Section III,27,(vii). 

Apparatus and procedure Closely similar to the preparation of tert.-Ci,H3MgCl, cyclohexyl-MgCl and cyclopentyl-MgCl (see Exp. 2). The yield (estimated from the results obtained from reactions with this reagent) is at least 90%. Here, too, it is essential to use M-butyl chloride which is free from butyl alcohol. 

The crude tosylate obtained after evaporation of the diethyl ether was dissolved In 150 ml of THF. After addition of 1 g of CuBr the solution was cooled to -10°C and a solution of tert.-butylmagnesium chloride in 250 ml of THF, prepared from 0.40 mol of -butyl chloride and magnesium (see Chapter II, Exp. 4) was added... 

The sedimentation and diffusion coefficients for three different preparations of poly(methyl methacrylate) were measuredf in /i-butyl chloride at 35.6 C (= 0) and in acetone at 20 C (> 0) and the following results were obtained ... 

A variant of the Wurtz reaction is the preparation of tetrabutyltin from activated magnesium chips, butyl chloride, and stannic chloride in a hydrocarbon mixture. Only a small amount of tetrahydrofuran is required for the reaction to proceed in high yield (86). 

There are only few reactions known introducing substituents to the H-bearing nitrogen of oxaziridines. (V-Alkylation of l-oxa-2-azaspiro[2.5]octane (3,3-pentamethylene-oxaziridine 52) with r-butyl chloride to give (53) was carried out for structure proof of (52). This reaction is of no preparative importance, since N-alkylated oxaziridines are easily obtained by ring synthesis. 

The general plan of Organic Syntheses has been discussed in the prefaces of the previous volumes. In this volume are published two distinctly different methods of preparation for each of two compounds. The directions for producing /3-chloro-propionic acid first from acrolein and second from trimethylene chlorohydrin, and for producing trimethylacetic acid first from terJ-butyl chloride and second from pinacolone, have been included. This has been deemed advisable since in some countries one raw material is more readily available than the other. 

Trimethylpyrylium perchlorate has been prepared from 2,6-dimethylpyrone and methylmagnesium halides 6 from mesityl oxide and sulfoacetic acid 6 from mesityl oxide (or less satisfactorily from acetone) and a mixture of acetic anhydride and perchloric acid 7 from mesityl oxide, acetyl chloride, and aluminum chloride 8 and from <-butyl chloride, acetyl chloride,... 

Generation in situ. Butyllithium (primary, secondary, or tertiary) can be generated by sonication of a mixture of lithium wire and a butyl chloride at 15° in dry THF. The corresponding butane is evolved under these conditions and LiCl precipitates the reaction is generally complete within 15 min. The highly useful lithium diisopropylamide can be prepared by sonication of a mixture of diisopropylamine, lithium, and butyl chloride in dry THF or ether. The yield is 91% and the solution can be used directly for deprotonation. Other lithium amides, even LiTMP, can be prepared in the same way. 

Priola, and Ferraris [36] had done what was considered impossible, namely to prepare a stable crystalline product from tert-butyl chloride and A1C13, and that they had used it to initiate polymerisation. From our own experiments we concluded independently that stable tert. aliphatic cations can be prepared and our discussion has been based on this view throughout. Our conclusion is derived from the following argument ... 

To prepare a THF solution of butylmagnesium chloride from butyl chloride, the procedure described by Olah and Arvanaghi (Olah, G. A. Arvanaghi, M. Org. Synth., Coll. Vol. VI11990, 451) for the preparation of 2-phenylethylmagnesium... 

More recent patents describe the following preparation from a-methylcinnam-aldehyde. a-Methylcinnamaldehyde (from benzaldehyde and propionaldehyde) is hydrogenated to a-methyldihydrocinnamic alcohol. The alcohol is alkylated with tert-butyl chloride or isobutene to 4-tert-butyl-o -methyldihydrocinnamic alcohol, which is subsequently dehydrogenated to the desired aldehyde [152, 153]. 

Preparative use could be made also from the perturbed redox catalysis (Eqs. (84)—(86), (93)-(95). For example, alkylated aromatic hydrocarbons that are difficult to obtain by Friedel-Crafts alkylation could be synthesized in this way. The most suitable alkylating agent is tert-butyl chloride or bromide -ass) alkyla-... 

The sec-butyl cation has been prepared by slow addition of jec-butyl chloride to SbFj-SOjCIF solution at - 110°C (Saunders Hagen Rosenfeld J. Am. Chem. Soc. 1968, 90, 6882] and by allowing molecular beams of the reagents to impinge on a very cold surface (Saunders Cox Ohlmslead J. Am. Chem. Soc. 1973, 95. 3018 Saunders Cox Lloyd J. Am. Chem. Soc. 1979,101, 6636 Myhre Yannoni J. Am. Chem. Soc. 1981, 103, 230). 

Silica gel is an effective catalyst for the t-butylation of thiophene and benzo[/ ]thiophene using t-butyl bromide. 2,5-Di-r-butylthiophene and 3-f-butylbenzo[b]thiophene can be prepared easily by this procedure (84JOC4161). Alkylation of thiophene with f-butyl chloride, isopropyl chloride or ethyl chloride at - 70°C in the presence of A1C13 produced a-complexes under kinetic control. On thermal equilibration, migration of alkyl from position 3 to position 2, as well as disproportionation to dialkyl-and trialkyl thiophenes can occur (86T759). 

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