Tertiary benzylamines

Treatment of a tertiary benzylamine also affords the Troc derivative with cleavage of the benzyl group (CI3CCH2OCOCI, CH3CN, 93% yield). ... 

Method B Powdered KMn04 (0.47 g, 3 mmol) is added to the tertiary benzylamine (l mmol) and TEBA-CI (0.68 g, 3 mmol) in CH2Cl2) (10 ml) and the solution is refluxed for 3 h, then cooled to room temperature, and stirred with aqueous NaHS03 (20%, 10 ml). The organic phase is separated, washed well with H20, dried (Na2S04), and evaporated to yield the amide. 

Treatment of tertiary benzylamines with acylating agents can lead to debenzylation. If the benzyl group is linked to an insoluble polymer, acylation and debenzylation will lead to the release of an acylated amine into solution (Entry 6, Table 3.9). These cleavage reactions generally yield products that are contaminated with acylating agent and so require further purification. 

Tertiary benzylamines react with chloroformate esters under acidic conditions to yield the corresponding benzyl chlorides (equation 173)1096. 

Treatment of a tertiary benzylamine also affords the Troc derivative with... 

The formation of ortho palladium products from a-aryl nitrogen derivatives and palladium salts is well known. Complexes formed from azobenzene, Schiff bases, tertiary benzylamines and oximes readily undergo insertion of CO into the metal-carbon bond to give, after work-up, a variety of heterocyclic compounds. Unfortunately, such reactions use expensive palladium salts in stoichiometric quantities. However, a number of related reactions have been shown to proceed in the presence of only catalytic quantities of palladium. Isoindolinones, for example, can be synthesized in good yield by reaction of o-bromoaminoalkylbenzenes with CO (100 C, 1 bar) in the presence of catalytic amounts of Pd(OAc)2, PPha and Bu"3N (equation 56). °... 

Carbamoyl chlorides. A direct preparation of carbamoyl chlorides from tertiary benzylamines (debenzylation) is by reaction with triphosgene. A-Methoxy-N-methyl-carbamoyl chloride, which is useful for coupling with various unsaturated organostannanes, is obtained from chloroformylation of the methoxylamine in the presence of pyridine. ... 

A. Cecchetto, F. Minisci, F. Recupero, F. Fontana, G. F. Pedulli, A new selective free radical synthesis of aromatic aldehydes by aerobic oxidation of tertiary benzylamines catalysed by N-hydroxyminides and Co(II) under mild conditions. Polar enthalpic effects. Tetrahedron Lett. 43 (2002) 3605. 

With cyclohexadiene as the H2 source tertiary benzylamines are cleaved in the presence of the henzyloxymethyl (BOM) group and benzyl ethers, but alkenes are reduced. ... 

De-N-benzylation. Tertiary benzylamines are transformed into the 0-(a-chloroethyl)carbamates in refluxing 1,2-dichloroethane. These carbamates are readily hydrolyzed by heating with methanol, giving the secondary amine hydrochlorides. 

Michaelis-Becker reactions have been carried out in two-phase systems even under such mild conditions, isomerization of prop-2-ynylphosphonic diesters occurs to give a 90% combined yield consisting of a mixture of diethyl propadienylphosphonate and diethyl-propy-l-nylphosphonate (85 15). Some of the allylic halides furnish small amounts of phosphonic esters, but others, and also benzyl halides, only undergo reaction in the presence of a long-chain tertiary amine hydrochloride catalyst. Dialkyl hydrogenphospho-nates and tertiary benzylamines react together to give dialkyl benzylphosphonates ". ... 

General procedure. Carbamoyl chlorides 221 from tertiary N-benzylamines 219 [135] A 0.3 M solution of the tertiary benzylamine (1 equiv.) in dichloromethane is added to a 0.1 M solution of triphosgene (0.33 equiv.) in dichloromethane at 0 °C under an inert atmosphere. The mixture is then allowed to warm to room temperature and stirred until no further change is seen by TLC. The reaction mixture is then concentrated under reduced pressure and the residue is purified by fiash chromatography. 

Tab. 4.49. Triphosgene-mediated transformation of tertiary benzylamines 1759 into carbamoyl chlorides 170 [135],...

The reaction of secondary and tertiary benzylamines with hydrazine in the presence of palladium catalyst (5% on carbon) was found to give toluene in yields greater than 85% . ... 

Thompson and Heck (1975) also prepared ortho palladium products of azobenzene (C), Schiff bases (CI CII), benzaldazine, acetophenone di-methylhydrazone, 1-methyl-l-phenylhydrazones, and tertiary benzylamines. These complexes, treated with carbon monoxide under mild conditions, gave a variety of interesting five-membered ring heterocyclic as well as open-chain products. Some examples are given in the following scheme ... 

Due to the acidic nature of phenol, carbonium ions are generated from these a-amino alcohols, which then interact with phenol to form secondary and tertiary benzylamine in a Mannich-type reaction containing chain molecules. This mechanism has been supported by the fact that the reaction rate increases considerably as the pH of the system decreases. Moreover, the presence of water and free phenol has been found to enhance the reaction rate to a great extent. The HMTA hydrolysis reaction and the formation of aminomethylene ions are the slowest reactions and are therefore considered to be the rate-determining step. Formation of oligomers results in the evolution of a gas which consists of about 95% NH3. The cured resin may contain up to 6% chemically bound nitrogen. 

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