F-butyl chloride

A successful procedure for the formation of 2,5-di-t-butylfuran involves reaction of the parent heterocycle with f-butyl chloride in the presence of iron(III) chloride and iron(III) oxide. Iron(III) oxide acts as a hydrogen chloride scavenger and at the same time regenerates the catalyst. Concurrent polymerization normally deactivates the catalyst (82CI(L)603). 

Fig. 4.11. Solvation changes during ionization of f-butyl chloride.

Trimethyl-l-pentene, methyl iodide, f-butyl chloride, r-butyl bromide (Matheson Coleman and Co.) and f-butyl iodide (Eastman Kodak) were obtained in highest purity and were distilled over calcium hydride or molecular sieves and stored at Dry-Ice temperature. 

Tertiary alkyl halides undergo a series of reactions when treated with hydrogen fluoride. f-Amyl chloride by means of reactions catalyzed by hydrogen fluoride yielded a series of teritary chlorides including f-butyl chloride (Simons et al., 35). t-Butyl chloride gives the same series of... 

The initiator-coinitiator complex BF3-OII2 is often shown as H+(BF3OH). Initiation by aluminum chloride and f-butyl chloride is described by... 

There are only few reactions known introducing substituents to the H-bearing nitrogen of oxaziridines. JV-Alkylation of l-oxa-2-azaspiro[2.5]octane (3,3-pentamethylene-oxaziridine 52) with f-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. 

There is direct evidence, from ir and nmr spectra, that the f-butyl cation is quantitatively formed when f-butyl chloride reacts with A1CI3 in anhydrous liquid HCI.246 In the case of olefins, Markovnikov s rule (p. 750) is followed. Carbocation formation is particularly easy from some reagents, because of the stability of the cations. Triphenylmethyl chloride247 and 1-chloroadamantane248 alkylate activated aromatic rings (e.g., phenols, amines) with no catalyst or solvent. Ions as stable as this are less reactive than other carbocations and often attack only active substrates. The tropylium ion, for example, alkylates anisole but not benzene.249 It was noted on p. 337 that relatively stable vinylic cations can be generated from certain vinylic compounds. These have been used to introduce vinylic groups into aryl substrates.250... 

The reaction of ZrCU with f-butyl chloride and phosphorus(IH) chloride in carbon disulfide gives [MesCPCyfZ CU] as a moisture-sensitive, insoluble solid. IR and Raman spectra of the anion are consistent with a D3h structure in which two ZrCU octahedra share a common face v(Zr—Cl terminal) 350-387, v(Zr—Cl bridging) 240-315 cm-1.613... 

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). 

Benzo[6]furan may be alkylated with f-butyl chloride and zinc chloride, the products being the 2- and 3-substituted compounds in the ratio 1 2. Benzo[6]furan is chloromethylated at the 2-position. 2-Methyl- and 2-phenyl-benzo[6]furan are chloromethylated in the 3-position. 

Friedel-Crafts alkylation of 2,5-dimethylthiophene with f-butyl chloride and A1C13 gave only the mono-r-butylated product (49) and none of the expected di-f-butylated thiophene (50). In order to facilitate di-r-butylation at positions 3 and 4, the substituents at 2 and 5 were tied back in the thiophenophane (51). This on alkylation gave, unexpectedly, the rearranged mono-f-butyl derivatives (52 30%) and (53 57%), and the di-f-butyl derivative (54 12%). The structures of the products were proved by NMR, Raney nickel desulfurization and independent synthesis (75T2551). One other such isomerization under Friedel-Crafts conditions had been previously reported (65JOC1058) 2,5-di-f-butylthiophene isomerizing to 2,4-di-f-butylthiophene. 

An example of the first isolated (3 -sultine makes use of this y-cyclization where f-butyl chloride formally acts as the leaving group (73JA3420,75CC724). Of the 13 examples reported, all eliminate S02 readily to give the corresponding alkenes in 50-90% yields (Scheme 72). 

This is essentially the procedure actually followed. Alkylation was effected, however, not with te/f-butyl chloride and aluminum chloride but with 2-methylpropene and phosphoric acid. 

Solution of antimony pentafluoride in anhydrous HF was found to be an efficient medium for alkylation reactions of fluoroolefins. Compounds, known to give stable carbocations in superacidic media are excellent alkylating agents. For example, f-butyl chloride (57) reacts with TFE, giving the corresponding alkane 58 ... 

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 f-butyl chloride, acetyl chloride,... 

The much more common case of hydrolysis reactions, which seem to correspond to the intermediate case of Eq. (XVI.1.4) with feCX ) = kz(H20)j is difficult to classify with certainty because, with the increase in salt content of the system, there is an increased tendency toward ionization (i.e., increase in Xion = ki/k2 due to increased ionic strength), which tends to compensate for the mass-law retardation. Because of these ambiguities, other approaches have been employed to throw light on the mechanism. One of these is to study stereochemical changes of RX during reaction, while another is to study competitive reaction of the intermediate R+. Thus f-butyl chloride in formic acid solution exchanges with radio-... 

It has already been mentioned that Kennedy s work showed that f-butyl chloride and trimethylaluminium do not interact in -pentane, although some residual mdisture must have been present in these non-rigorously dried media. The reaction oreurs as K n as some methyl chloride is added to the system and this phenomenon has been attributed to the breaking down of the trimethylaluminium dimers and formation of an active methyl chloride-trimethylaluminium complex. Thus, the role of water in these interactions seems negligible or absent. 

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