Polymethylene diamines

The rate of deamination is determined by the chain length and with polymethylene diamines, NH2-(CH2)n-NH2, the maximum rate occurs when n = 4 (putrescine) and n = 5 (cadaverine) and decreases to zero when n = 9 or more. At this chain length, MAO becomes active and can oxidatively deaminate the diamines. It should be noted that although MAO can deaminate both substituted and primary amines, DAO can deaminate only primary amines. 

Grignard reagents which have been prepared from polymethylene halides and magnesium in the presence of 0.1% water in the ether react readily with O-methylhydroxylamine to form the corresponding polymethylene diamines (50-68%). ... 

The introduction of stereogenic centers in this type of gelator results in new morphologies of gel fibers such as twisted ribbons and coiled coils. Chiral diamides 29-Me and 30-Me were prepared by acylation of the a,co-polymethylene diamines with (2S)-2-methyldodecanoyl chloride in a two-phase ether-water system in the presence of sodium bicarbonate (Scheme 8). Formation of twisted ribbons and coiled coils was explained by chiral van der Waals interactions between terminal aUcanoic chains induced by introduction of chiral centers. 

Biogenic amines, biological amines biologically and pharmacologically important naturally occurring amines, occurring widely in plants and animals. They can be divided into 1. derivatives of ethanolamine, e.g. choline, acetylcholine, muscarine 2. polymethylene diamines, e.g. putrescine, cadaverine 3.polyamines, e.g. spermine 4. imidazolylalkylamines, e.g. histamine 5.phenylalkylamines, e.g. mescaline, tyra-mine, hordenine 6. catecholamines, e. g. adrenalin, nor-adrenalin and dopamine 7. indolylalkylamines, e.g. tryptamine, serotonin and 8. betaines, e.g. carnitine. 

Estimated HCl production during isocyanate manufacture represents net HCl. This value excludes HCl consumed ia the reaction process to make methylene diphenylene diamine (MDA) and polymethylene polyamine (PMPPA) iatermediates ia the production of 4,4 -methylenebis(phenyHsocyanate) (MDl) and polymethylene polyphenyHsocyanate (PMPPl). 

MDI and its polymers are synthesized in two steps. The first yields diphenyimethane diamine or polymethylene polyphenyl amines, and the second consists of the phosgena-tion of the amine obtained. 

The concentration at which lyotropic phase is formed depends on the chemical stmcture and molecular mass of the polymer, the solvent nature, and the temperature. Generally, the effective concentration is in the range 10-20% by weight of the polymer in the solvent at room temperature. All polyamides form nematic lyotropic solutions, and the introdurtion of either a lateral substituent on the diamine, or of 1,3-phenylene units (in very small amoimts) or of flexible spacer (espedally polymethylene fragments) can increase the solubility of the polymers in the less a ressive solvent. 

Filming" amines, such as polymethylene imines and diamines, almost certainly undergo reduction on the surface protonation may very well be involved as an initiating step. Quaternary nitrogen salts may also undergo reduction reactions, but there currently is no evidence to that effect. 

Nishimoto S, Ohtani B, Yoshikawa T, Kagiya T (1983) Photocatalytic conversion of primary amines to secondary amines and cyclization of polymethylene-a, co-diamines by an aqueous suspension of titanium (IV) oxide/platinum. J Am Chem Soc 105(24) 7180-7182... 

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