Pentamethylene oxide

Chemical Name 1,5-epoxypentane, pentamethylene oxide, oxacyclohexane, tetrahydro-2H-pyran... 

Pentamethylene Bromide (Coll. Vol. i, 419) Tetrahydrofurfuryl alcohol passed over alumina at 370-380 gives 1,2-dihydropyran in 44 per cent yield. Hydrogenation in the presence of platinum produces pentamethylene oxide (1,5-epoxypentane), which is converted to the bromide by heating with hydrogen bromide in glacial acetic acid. Ibe yield is 65 per cent, based upon r,2-dihydropy-ran. Paul, Bull. soc. chim. [4] 53, 1489 (1933). 

Pentamethylene oxide is obtained in almost quantitative yield by the action of zinc and water on a,e-dibromopentane. ... 

The 6-membered (pentamethylene oxide) anhydro ring is present in methyl 2,6-anhydro-a-D-altroside 36) and in the naturally occurring 1,5-anhydrohexitols, styracitol and polygalitol. 

Chlorosulfonic acid reacts with a mixture of a long chain aliphatic carboxylic acid and pentamethylene oxide with cleavage of the cyclic ether, yielding a long chain alkyl sulfate 116 (Equation 45). ... 

More complicated structures without symmetry were named end to end. This method was partieularly appropriate for the poly(oxides) of the form -(R-O-R -O h (and for the analogous sulfides, sulfones, ureas, and anhydrides) and for the poly(o-amino acids) and for the poly (o-hydroxy aeids). The constitutional hydrocarbon subunits were ordered alphabetieally in naming the polymer as, for example, in poly(methyleneoxy pentamethylene oxide). 

---