N-Pentylamine

The adaptation of the Bischler-Napieralski reaction to solid-phase synthesis has been described independently by two different groups. Meutermans reported the transformation of Merrifield resin-bound phenylalanine derivatives 32 to dihydroisoquinolines 33 in the presence of POCI3. The products 34 were liberated from the support using mixtures of HF/p-cresol. In contrast, Kunzer conducted solid-phase Bischler-Napieralski reactions on a 2-hydroxyethyl polystyrene support using the aromatic ring of the substrate 35 as a point of attachment to the resin. The cyclized products 36 were cleaved from the support by reaction with i-butylamine or n-pentylamine to afford 37. 

The most important example of alkene elimination is found for ionized 1-pentylamine, for which propene loss is the dominant fragmentation of metastable ions. However, this channel is not of general importance metastable ionized 1-butylamine eliminates a much smaller proportion (15%) of ethylene and higher homologues of metastable ionized n-pentylamine rarely expel alkenes to any appreciable extent44. Nevertheless, [M — C H2 ]+ ions do appear in LELT spectra of long-chain primary alkylamines (e.g. at m/z 31, 45, 59, 73, 87 and 101 for 1-octylamine, Figure 2)113. 

A considerable increase in conversion of Morwell brown coal occurs when dilute sodium hydroxide was used in place of water (see Table VIII and Figure 8). Dilute sodium carbonate and formate had a similar effect (see Table VIII) as did n-pentylamine (see Table IX), but no improvement was found with dilute hydrochloric acid, sodium chloride or ammonium hydroxide nor with 20% phenol/80% water and methanol/water mixtures. The conversion and extract yield increases with the molarity of the sodium hydroxide (Figure 8). 

TABLE IX. Conversions for Extraction of Yallourn Coal with n-Pentylamine (Method A)... 

Disulfide bonds present in the keratin of hair are potential binding sites for many nucleophilic molecules. Tolgyesi and Fang investigated the structural changes which occur in keratin as a result of alkaline treatments of hair. They reported that hydroxide ions initiated a p-ehmination reaction, resulting in cleavage of the disulfide bonds of cystine to produce dehydroalanine intermediates. Cysteine and lysine may react with dehydroalanine to form new cross links in keratin. Nucleophilic amines such as ethylamine and n-pentylamine may also react with dehydroalanine to form... 

SYNS AMN METHYLAMYLNITROSAMN (GERMAN) METHYLAMYLNITROSAMINE METH-YL-N-AMYLNITROSAMINE N-METHYL-N-NITROSO-PENTYLAMINE METHYL-N-PENTYL-NITROSAMINE N-NITROSO-N-METHYL-N-AMYL-AMINE NITRO-SOMETHYL-N-PENTYLAMINE... 

SYNS l-AMINOPENTANE AMYLAMINE AMYLAMINE (DOT) n-AMYLAMINE MONOAMYLAMINE NORLEUCAMINE 1-PENTANAMINE PENTYL-AMINE n-PENTYLAMINE... 

Other derivatives of heparin have been reported to have a crystalline appearance for example, the salts formed wdth piperidine, n-pentylamine, and isopentylamine. Dodecylamine and decamethylenediamine have also been used in the preparation of heparin. 

In hdn of pyridine (643 K, 136 atm) over asulphidedNiO(3.5)-Mo03(18)/ AI2O3 catalyst conversion kinetics and intermediates were consistent with a mechanism in which nitrogen elimination is preceded by ring hydrogenation and some dipentylamine is formed by elimination of NH3 between two molecules of n-pentylamine. ... 

It can be seen that an agitated medium is markedly favourable to the TON-type zeolite, the FER-type zeolite being less sensitive to this factor. The presence of seeds increases the crystallization rate for both zeolites. FER-type zeolites containing Co2 or Mg2 could be prepared with Co2 or Mg2 - ezchanged aluminosilicate gels (20). In addition to the above-mentioned templates for TON-type zeolites, two other amines, di-n pentylamine and 1,4-diamino n-pen-tane, yield the same structure. 

Add di-n-pentylamine to solution (3) with stirring, and then stir the solution for 30 min ... 

All the common HDN schemes of e.g. pyridine require, after prehydrogenation a first ring-opening C-N bond breaking, followed by the decomposition of n-pentylamine to remove the nitrogen as NH,. It is also possible to envisage pathways or steps that involve extrusion of nitrogen from related molecules such as imines and amides, and therefore it is of interest to consider at this point some reactions of such substrates induced by transition metal complexes. 

In the case of HDN, an additional interesting possibility also consistent with the heterolytic mechanism arises, since substrates like the pyridines -or intermediate alkyl or aryl amines- are sufficiently basic to promote the activation of hydrogen so as to form a metal hydride plus a protonated base (e.g. a pyridinium or an alkylammonium cation). Furthermore, some of the most widely accepted amine HDN mechanisms include the initial protonation of the amine nitrogen, followed by elimination of ammonia from the ammonium cation. Therefore, it is very easy to combine the idea of a heterolytic hydrogen activation promoted by, say n-pentylamine, with a subsequent degradation by a Hoffmann mechanism, to conform a reasonable HDN catalytic cycle. A simplified representation of this idea is given in Fig. E4. 

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