Linear amines

The reaction can be combined with an alkene isomerization, which requires the use of the more electron-withdrawing XANTPHENOXAPHOS ligand. Thus, starting from internal alkenes, linear amines can be obtained in quite reasonable yields and high n/iso selectivity (Scheme 15) [60]. 

Scheme 15.13 Hydroaminomethylation of terminal alkenes to linear amines.

Table 2.2 presents the dissociation constants for linear amines. Here, the values of pkjiss converge to about 10.64 for large n. 

The complex sorption behavior of the water in amine-epoxy thermosets is discussed and related to depression of the mechanical properties. The hypothesized sorption modes and the corresponding mechanisms of plasticization are discussed on the basis of experimental vapor and liquid sorption tests, differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and dynamic mechanical analysis. In particular, two different types of epoxy materials have been chosen low-performance systems of diglycidyl ether of bisphenol-A (DGEBA) cured with linear amines, and high-performance formulations based on aromatic amine-cured tetraglycidyldiamino diphenylmethane (TGDDM) which are commonly used as matrices for carbon fiber composites. 

Waters SP-8HR (strong cation exchange, 8 /r particles) Linear amines (spermine, spermidine, triethylene tetramine, diethylene triamine, tetraethylene pentamine) low molecular weight branched aromatic and nonaromatic dendrimers (e.g., PETMA4, DPE-TMA6, PE-DMABzCl4) rHu-BDNF (recombinant human brain-derived neurotrophic factor) 51... 

The starting linear amine, N, IV -bis(3-aminopropyl)-l, 3-propanediamine, is prepared using the procedure for N,A -bis(2-aminoethyl)-l,3-propanediamine,2 which consists of the condensation of 1,3-dibromopropane with 1,3-diamino-propane. The resulting amine is purified by vacuum distillation from barium oxide, bp 135-136° at 1 torr, 65-70% yield. The tetraamine forms a solid hydrate when exposed to moist air its tetrahydrochloride decomposes at 297°. 

The tetratosylate of the linear amine is prepared by the dropwise addition of 477 g (2.5 mole) of p-toluenesulfonyl chloride dissolved in 2.5 L of diethyl ether to a solution of 80 g (2 mole) of sodium hydroxide and 94.2 g (0.5 mole) of the linear tetraamine in 200 mL of water. The mixture is vigorously stirred by a mechanical stirrer during the addition and for an hour after its completion. The resulting sticky paste is chilled in an ice bath and then removed by filtration. It is washed well with diethyl ether and water and thoroughly dried in a vacuum at 50° to obtain a clumpy white powder. After recrystallization from methanol, 300-350 g (70-90%) of the tetratosylate is obtained, mp 126-127°. 

The precipitate is removed by filtration, washed with diethyl ether, and dried thoroughly. It is then dissolved in the minimum amount of water and brought to pH > 10 (Hydrion paper) with sodium hydroxide. Any precipitate is removed by filtration and the filtrate is extracted four times with equal volumes of dichloro-methane. The dichioromethane extracts are dried with anhydrous sodium sulfate and evaporated to dryness leaving a light-yellow solid. The crude product is sublimed ( 60°, 0.01 torr) to yield 12-14 g (55-60% on the basis of tetratosylated linear amine) of white crystals, mp 84° (lit.8 82-83°). 

Diphenyl-l,4-diazacyclododecan 26 was prepared by the zinc reduction of bis(imine) formed from linear amine and benzaldehyde (Equation 2) <1995JOC3980>. 

Compound 53 is a key intermediate in another effective method for cyclen 1 production <1996JOC5186, 20010S(78)73>. The method employs dithiooxamide for rigidifying of linear amine 2,2,2-tet and reduction of 53 (Scheme 8) (see Chapter 11.16) 2,2,9,9-Me4-cyclen was prepared by analogous way from linear 2,2,9,9-Me4-2,2,2-tet (12% overall yield) <2002ICA45>. 

Cyclic sulfides are known to be less basic than linear sulfides. Because the equilibrium constant K (Eq. (38)) is small, trialkylsulfonium ions cannot be used as initiators for the polymerizar tion of cyclic sulfides l. The relation between cyclic and linear amines resembles that of sulfides rather than etha s. In some cases, however, ammonium ions have been successfully used as initiators, e. g. in the polymerization of conidine or l-benzylaziridine l. 

Ammonia was oxidized with hydrogen peroxide in the presence of TS-1 first to hydroxylamine and then, further to nitrogen oxides if the hydroxylamine was not trapped. When this reaction was run in the presence of a ketone, the oxime was selectively formed (Eqn. 21.8).33 Oximes were also produced by the oxidation of primary aliphatic amines with TS-1 or TS-2 and hydrogen peroxide at ambient temperature. Linear amines such as n-propyl amine (6) gave the oxime in 73% yield at 32% conversion over the TS-1 catalyst (Eqn. 21.9).3 The isopropyl amine (7) was oxidized with somewhat higher selectivity over the larger pore TS-2 catalyst (Eqn. 21.10).34 Primary aryl amines were oxidized to the symmetrical azoxybenzenes under these conditions (Eqn. 21.11). ... 

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