Morpholine, A/-

Fig. 2. Observed vs. calculated rates of hydrolysis of enamines at 24.8°. Drawn lines calculated log k values. Observed values o for 4-(2-methylpropenyl)morpholine A for l-(2-methylpropenyl)piperidine for l-(2-methylpropenyl)pyrrolidine. Values are corrected for buffer contributions (23).

The kinetic comparison of amination of the chloropyridines is incomplete due to the intervention of acid catalysis. The reaction of 2-chloropyridine with piperidine shows a constant rate coefficient as the reaction proceeds to completion, but, with the less basic morpholine, a rising coefficient indicative of acid catalysis is observed. 4-Chloropyridine exhibits a rising rate coefficient even with piperidine. ... 

The reagent is toxic and expensive but these disadvantages are minimized by methods that use only a catalytic amount of osmium tetroxide. A very useful procedure involves an amine oxide such as morpholine-A-oxide as the stoichiometric oxidant.41... 

Aminocarbonylation can also be carried out by use of CO and a silyl amide. Watanabe et al. reported the cobalt-catalyzed aminocarbonylation of epoxides [55]. Some silyl amides such as PhCH2NHSiMe3 and Et2NSiMe3 were applicable to the reaction to give the /i-siloxy amide in good yields, whereas high reaction temperature was required. The use of 4-(trimethylsilyl) morpholine was found to be crucial for a milder and more efficient carboami-nation here, the reaction proceeded at ambient temperature under 0.1 MPa of CO. However, N-(2-hydroxyalkyl)morpholines, a product without carbonyla-tion, were yielded as by-products (Scheme 18) [56]. 

Since the reagent is quite expensive, different catalytic procedures have been developed. A very useful procedure involves an amine oxide, such as morpholine-A-oxide, as the stoichiometric secondary oxidant (Scheme 10.4) [29]. 

Hydroxymorpholine. see Morpholine a-Hydroxymuconic acid, see PCB-1221 a-Hydroxymuconic semialdehyde, see Benzene... 

In an experiment, hatchery-reared Coho salmon have been imprinted to the artificial odors of morpholine, a heterocyclic amine (C4H9NO 5 x 10 mg/l) ... 

From the pATa values shown, there is relatively little difference in basicities for diethylamine, pyrrolidine, or piperidine. Note, however, that morpholine and piperazine are weaker bases than piperidine. This is the result of an electron-withdrawing inductive effect from the second heteroatom, making the nitrogen atom both less basic and also less nucleophilic. This makes morpholine a useful base with basicity between that of piperidine and pyridine pK 5.2) (see Section 4.6). The second pK value for the diamine piperazine is substantially lower than the first, since the inductive effect from the protonated amine will withdraw electrons away from the unprotonated amine (see Section 4.7). 

Diethylene and triethylene glycol (DEG and TEG) are produced as byproducts of ethylene glycol. DEG and TEG are used in polyurethane and unsaturated polyester resins and in the drying of natural gas. DEG is also used in antifreeze and in the synthesis of morpholine, a solvent, corrosion inhibitor, antioxidant, and pharmaceutical intermediate. 

A more recent process for producing regenerated cellulose involves the use of V-methyl-morpholine-A-oxide, a highly polar solvent, at about 130°C to dissolve cellulose [Rosenau et al., 2001], About 5% of all regenerated cellulose is produced by this method. 

The alternative selective cleavage of the allyl ester was achieved by Pd(0)-catalyzed allyl transfer. Because the Fmoc group is sensitive to morpholine, a very weak base must be used as the allyl-trapping nucleophile. IV-Methyl aniline was favorable, and its use as a scavenger nucleophile gave rise to the acid 29 in a high yield. 

Hydrogenated derivatives of the monocyclic and bicyclic oxazines and thiazines are also very well established compounds and a number are so familiar that they too have trivial names. Tetrahydro-l,4-oxazine, for example, is better known as morpholine, a name first allocated to it because of a supposed, but erroneous, relationship to the alkaloid morphine. By analogy the corresponding thiazine is called thiomorpholine or sometimes thiazane. 

A milestone in the routine employment of perruthenate in the oxidation of alcohols was established with the publication by Griffith, Ley et al. in 1987 on the catalytic use of tetra- -propylammonium perruthenate (TPAP).11 The presence of the tetra- -propylammonium cation renders this compound soluble in apolar media and allows the existence of a high concentration of perruthenate ion in organic solvents. The tetra- -propylammonium perruthenate is easily prepared and can be employed catalytically in CH2CI2 solution in the oxidation of alcohols to ketones and aldehydes, using /V-methyl morpholine A-oxide (NMO) as the secondary oxidant. 

From the sequential reaction of 4-chromanones 251 with thionyl chloride, thioacetic acid, and morpholine, a mixture of thioxochroman-4-one 252 and its. Y-sulfide 253 can be obtained (actually they can disproportionate). By cycloaddition, stereoisomeric 1,2,4-trithiolane derivatives 254 and 255 have been obtained the R1, R2 groups in Scheme 78 can actually be derived from cyclanones < 1998JOC9480>. 

A one-sided binding of the complex to the support resulted in further improvements (92). This requires synthesis of nonsymmetric salen-type ligands, which is complicated by the tendency of such ligands to equilibrate to give mixtures containing symmetric Schiff bases. Excellent results were obtained with monomer 7d, diluted in a methacrylate polymer, by using a combination of meta-chloroperbenzoic acid (mCPBA) and A-methyl-morpholine-A-oxide (NMO) as the oxidants ... 

Although 0s04 is thought of as a specific oxidant for cis alkenes there are a few examples of hydroxylation of trans alkenes, e.g. cis- and frans-cyclodecene can be hydroxylated to the respective cis and irons diols.597 The Os04-alkene-pyridine reaction can be made catalytic by the use of suitable secondary oxidants such as H202, C103 , Bu OOH, A-morpholine A-oxide, I04 , 02 and CIO-. S54... 

A very broad class of primary oxidants act as oxygen atom transfer agents, the most widely nsed oxidants in oxidation catalysis. These inclnde peracids or their anion forms, snch as MCPBA or oxone (O-OSOs ) as well as A-oxides snch as A-methyl morpholine A-oxide or hypochlorite ion. They all have general structure XO, where X is a good leaving gronp. 

Aryl-3-chloro-l,2-dithiolium ions react with various secondary amines (morpholine, A-alkylanilines, diarylamines) to give 3-amino-5-aryl-l,2-dithiolium ions (41) which may also be considered as iminium derivatives (42). ... 

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