Halomethyl octyl ethers: Convenient halomethylation reagents

Abstract

Chloromethylmethyl ether (CME) and bis-chloromethyl ether (BCME) are very convenient and efficient chloromethylating reagents, yet they are listed as carcirogens.' BCME is more notorious than CME. Consequently, several attempts have been made to synthesize CME free of BCME,, or iodomethyl-methyl ether free of BCME,3 or to introduce alternative reagents such as methylal/chlorosulfonic acid,4 or to generate incipient halomethyl furonium ion from l-chloro-4-chloro-(bromo)methoxy butane and 1,4-bis-[chloro(bromo)methoxy b~t a n e ] . "~ Short-chain chloromethyl-alkyl ethers were studied in the alkylation of aromatic compounds, but not as chloromethylating reagent^.^ Long chain chloromethylalkyl ethersgJO were described as intermediates on the way to cationic surfactants'J2 or alkoxymethyl sucrose surf act ant^.'^ No attention was given to their use as halomethylating agents or to the generation of BCME during their preparation. RESULTSWe wish14 to report the BCME-free synthesis of long chain halomethylalkyl ethers, ROCH,X, and their application in halomethylation of aromatic substrates and polymers, according to the following reactions:

Novel polymer-supported β-dithioketonate nickel catalysts for selective propylene dimerization

“…DOW-C resin was chloromethylated as previously reported [20] to afford a 20 mol% content of functionalized co-units, the resulting chloromethylated resin containing 6 wt% Cl (1.7 meq of Cl/g). Some 10 g of chloromethylated DOW-C resin (17.0 meq of Cl), suspended under dry argon in 300 ml of anhydrous DMF, were swelled by stirring for 8 hr at room temperature.…”

Synthesis and Properties of Interpenetrating Polymer Networks Composed of Epoxy Resins and Polysulphones with Cross-linkable Pendant Vinylbenzyl Groups

“…But chloromethyl methyl ether is a notorious carcinogen, so haloalkyl alkyl ethers having longchain alkyl groups have been investigated as safer reagents. 26,27 In this study, CMOE was used as a much less volatile reagent than the classical one. Table 1 shows some characteristics of the chloromethylated polysulphones (PSF-CM).…”

“…Chloromethyl octyl ether (CMOE) was prepared according to the method of Warshawsky et al 26,27 Typical procedures are brieÑy described.…”

Novel polymer-supported β-diketonate nickel catalysts for α-olefin activation

“…4): (4) Dow C resin was chloromethylated as previously reported [12] to afford a 45 mol% content of functionalized units. Some 3.4 g of chloromethylated Dow C resin (12 meq of Cl) were suspended in 100 ml of DMF, stirred for 2 hr and then slowly added to 3 g (13.1 mmol) of sodium hexafluoroacetylacetonate.…”