Pentamethylene

Trimethylene dibromide (Section 111,35) is easily prepared from commercial trimethj lene glycol, whilst hexamethylene dibromide (1 O dibromohexane) is obtained by the red P - Br reaction upon the glycol 1 6-hexanediol is prepared by the reduction of diethyl adipate (sodium and alcohol lithium aluminium hydride or copper-chromium oxide and hydrogen under pressure). Penta-methylene dibromide (1 5-dibromopentane) is readily produced by the red P-Brj method from the commercially available 1 5 pentanediol or tetra-hydropyran (Section 111,37). Pentamethylene dibromide is also formed by the action of phosphorus pentabromide upon benzoyl piperidine (I) (from benzoyl chloride and piperidine) ... 

Pimelic acid. Heat a mixture of 18 g. of pentamethylene dicyanide and 250 g. of 50 per cent, sulphuric acid by weight in a 750 ml. round-bottomed flask under reflux for 9 hours. INIost of the pimehc acid separates from the cold reaction mixture. Filter oflF the crystaUine acid upon a sintered glass funnel. Saturate the filtrate with ammonium sulphate and extract it with three 50 ml. portions of ether. Dissolve the residue on the filter (which is shghtly discoloured, but is fairly pure pimehc acid) in the combined ethereal extracts, dry with anhydrous sodium or magnesium sulphate, and remove the ether by distiUation. Recrystallise the residual sohd acid from benzene containing 5 per cent, of ether. The yield of pure pimehc acid, m.p, 105-106°, is 22 g. 

Compositions is mix of pentamethylene hexaurea (PMHU) [35710-96-4] and higher molecular-weight urea. 

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. 

H-Benzimidazole, 2,2-pentamethylene-reduction, 5, 423 Benzimidazole-2-carbaldehyde oximes, 5, 436 Benzimidazolecarbaldehydes oxidation, 5, 437 Benzimidazole-2-carbamates 5-substituted as anthelmintics, 1, 202 Benzimidazole-1-carboxylic acid, 2-amino-methyl ester reactions, 5, 453... 

Pentandiol has been prepared by the reduction of methyl glutarate. and by the reduction of epoxy-1,5-peiitanol-5. It has also been prepared from pentamethylene bromide by conversion to the cliacetate followed by hydrolysis to the glycol. The procedure described is a modification of that of Connor and Adkins. ... 

Chemical Designations - Synonyms Pentamethylene Chemical Formula CjHk,. 

Molecular weight determinations have been carried out with methyl-ethyl-, diethyl-, di-n-propyl-, pentamethylene-, and methylphenyl-diazirine. They gave monomeric molecular weights. The three last-named compounds gave the calculated C, H, and N values by the usual procedure of microanalysis. 

The reaction with A -cyclohexylidenepyrrolidinium perchlorate (101a) is particularly interesting 2,2-pentamethylene-l,l-tetramethyl-eneaziridinium perchlorate (101b) is formed in 88% yield. ... 

A solution of tetrahydropapaverine (4.43 g) and 1,5-pentamethylene diacrylate (1.30 g) in dry benzene (15 ml) was stirred under reflux for 4B hours excluding light. The solvent was removed in vacuo and the residual pale red oil dissolved in chloroform (10 ml). Addition of ether (ca 400 ml), followed by saturated ethereal oxalic acid solution (ca 500 ml) gave a floc-culent white precipitate, which was filtered off, washed with ether and dried. Crystallization (twice) from ethanol gave N,N -4,10<)ioxa-3,11 <)ioxotridecvlene-1,13-bis-tetrahydropapa-verlne dioxalate as a white powder (3.5 g 51% MP 117°to 121°C). 

DPTS-di-pentamethylene thiuram tetrasulfide TDD-thiodiazoIe derivative NC-fatty acid amide amine B-18-special curative DOTG-dior-tho-tolyl guanidine peroxide 14/40-dicumyI peroxide TAC-triallyl cyanurate. 

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