Morpholine, structure

Figure 6, which displays the projections down the respective C—N bonds, demonstrates that the pyramidality at the nitrogen atom varies over the whole range from virtually complete tetrahedralization to virtual planarity (sp2-hybridized N). The pyramidality is greater for molecules where the N-atom is part of a six-membered ring (piperidine or morpholine, structures 17, 18 and 19) and smaller for molecules where the N-atom is part of a five-membered ring (pyrrolidine). 

Dibenz[h,e]azepine-6,11-diones ent-Morphinan nomenclature, 1, 29 Morphinan, 1,2,3,4-tetrahydro-nomenclature, 1, 29 14-a-Morphinan, N-methyl-synthesis, 1, 480 Morphinans nomenclature, 1, 29 as pharmaceuticals, 1, 148 synthesis, 2, 377 Morphine, 2, 512 as analgesic, 1, 167 as metabolite of normorphine, 1, 235 as pharmaceutical, 1, 146, 147, 148 synthesis, 1, 480 Morphine alkaloids structure, 4, 534 Morphin-7-en nomenclature, 1, 29 Morphinone, dihydro-as pharmaceutical, 1, 147 Morpholine — see also 1,4-Oxazine, tetrahydrocarcinogenicity, 1, 229 corrosion inhibitor, 1, 409 metabolism, 1, 226 nomenclature, 3, 996 structure, 2, 5 synthesis, 2, 89 Morpholine, 4-aciyloyl-polymers, 1, 291 Morpholine, alkenyl-polymers, 1, 291... 

Enamines formed in this way may be distilled or used in situ. The ease of formation of the enamine depends on the structure of the secondary amine as well as the structure of the ketone. Thus pyrrolidine reacts faster than morpholine or piperidine, as expected from a rate-controlling transition state with imonium character. Six-membered ring ketones without a substituents form pyrrolidine enamines even at room temperature in methanol (20), and morpholine enamines are generated in cold acetic acid (21), but a-alkylcyclohexanones, cycloheptanone, and linear ketones react less readily. In such examples acid catalysis with p-toluenesulfonic acid or... 

A few computational studies focus on the saturated analog of 4//-l,4-oxazine, i.e., morpholine [98JCS(P2)1223, 00JCS(P2)1619, 00TL5077]. These cover the structure of lithium morpholide, cycloaddition reactions, and molecular complexes with genistein. 

A variety of inorganic (31,87) and organic bases have been added to the catalyst to improve selectivity. The effectiveness of organic bases is very sensitive to structure. Morpholine is an effective inhibitor, more so than /Si-melhylmorphollne > N-elhylmorpholine > 3,5-dimethylmorpholine (55). Piperazine is effective, but ethanolamine and ethylenediamine are poisons. 

Chemical Name 4-[3-(4-Butoxyphenoxy)propyl] morpholine hydrochloride Common Name Pramocaine hydrochloride proxazocain hydrochloride Structural Formula ... 

Fig. 9.3 Absorption spectra of panal in methanol (A), and in 18% acetonitrile/water (v/v) containing 20mM morpholine and acetic acid, pH 4.3 (B). The absorption peak in A is broad due to the partial enolization of the keto group forming a conjugated structure C=C-C=C-OH. In B, the C=0 group is completely converted into an enamine (C=C-C=C-NR2) by morpholine, giving a sharp absorption peak. From Shimomura, 1989, with permission from the American Society for Photobiology.

Dithiocarbamate complexes of copper have been sythesized at a high rate. Reports of new complexes include the morpholine-4- (44), thio-morpholine, AT-methylpiperazine-4-, and piperidine- (291) dithiocarba-mates. Novel, polymeric complexes of the type Cu(pipdtc)2 (CuBr) in = 4, or 6) and Cu(pipdtc)2 (CuCl)4 have been prepared by reactions of[Cu(pipdtc)2] with the respective copper halide in CHCla-EtOH (418). The crystal structures of the polymers are known to consist of sheets of individual [Cu(pipdtc)2] molecules linked to polymeric CuBr chains via Cu-S bonds. A series of copper(I) dtc complexes have been the subject of a Cu and Cu NQR-spectral study (440). 

Preparation of Reagent and Labelling Procedures. The structure of F-D [2-(2,4-diazobicyclo-2,2,2-octyl)-4-(5-aminofluoresceinyl)-6-morpholinyl 1,3,5-triazine] has been confirmed by its FAB-MS, IR, and H-NMR spectra (9). Briefly, F-D was synthesized by the treatment of fluorescamine isomer I with cyanuric chloride, then reaction with morpholine and DABCO (l,4-diazobicyclo-2,2,2-octane), as illustrated... 

Now let us consider Structure 6.21 and Spectrum 6.18 and see how the Karplus curve can be used to aid assignment of the spectrum. (This compound will be referred to from now on as the morpholine compound as we will use it to demonstrate several different techniques) Note that the aromatic region has been omitted as it contains little of interest and we wish to concentrate on the carbocyclic region of the spectrum. It was acquired in CDCI3. 

To synthesize new surfactants, having incorporated both structural elements, the known siloxanyl modified halogenated esters and ethers of dicyclopentadiene [5] were treated with different amines according to the reaction scheme. Triethylamine yielded quaternary ammonium salts directly. Alternatively, after reaction with diethylamine or morpholine, the isolated siloxanyl-modified tertiary amines were also converted to quaternary species. To obtain anionic surfactants, the halogenated precursors were initially reacted with n-propylamine. In subsequent reaction steps the secondary amines formed were converted with maleic anhydride into amides, and the remaining acid functions neutralized. Course and rate of each single reaction strongly depended on the structure of the initial ester or ether compound and the amine applied. The basicity of the latter played a less important role [6]. 

If mono-hydroxyl functionalized polyethylene glycol), HO-PEG, is added to Ca(NTMS2)2.THF2, then addition of LA affords the diblock PEG-b-PLA (Mn= 15,500, Mn calc = 15,500, Mw/Mn = 1.03).832 Using a similar strategy the reaction of CaFI2 with telechelic diol HO-(PEG)-OH, followed by polymerization of L-LA results in a triblock structure, PLA-b-PEG-b-PLA of narrow polydispersity (1.02-1.08).835 836 Triblock copolymers of morpholine-2,5-diones with PEO have also been prepared in this manner.837... 

The initiating nucleophile in the vast majority of these studies is the hydroxide anion. However, in principle, any nucleophile can add to the keto or formyl group to give rise to an anionic intermediate, which then could act as an intramolecular nucleophile and effect hydrolysis of the ester. Their relative effectiveness will depend on two factors the relative extent of formation and the nucleophilicity of the adduct. The nucleophiles that have been investigated are hydroxide, cyanide, morpholine and piperazine. The only quantitative comparison available is that of hydroxide, morpholine and piperazine, which are effective in the order of ca. 102 10-3 1 (Bender et al., 1965 Dahlgren and Schell, 1967). For morpholine and piperazine this is as expected on the basis of their relative basicities. However, the expected order of increasing formation of the adducts would be cyanide > nitrogen bases > hydroxide (Hine, 1971). At this time, these results cannot be analysed further, but more work on the systems could enable the structural dependence and reactivity to be elucidated. 

Fig. 1 Schematic drawing showing the structure of tris(A/,AT-disubstituted-dithiocarbam-ato)iron(III). Substituents R1 and R2 represent various types of alkyl groups including those being part of the ring systems morpholine, pyrrolidine or pyrrole (Table 1)... 

Its chemical structure does not allow elimination of HNO, thus supporting the oxidative pathway of activation to NO, a mechanism still possible in this blocked SIN-1A derivative. The final product of the NO-release was found to be l-amino-2-cyanomorpholine (110) [106]. Its formation can be rationalized assuming that, after the oxidative NO-release, deprotonation occurs at the a-position of the morpholine, followed by migration of the cyano group and hydrolytic cleavage of the hydrazone moiety. 

Morpholine chromate, molecular formula, properties, and uses, 6 562t Morphology. See also Structure of carbon fibers, 26 737-739 of high density polyethylene, 20 162 of polymer blends, 20 356 of polymer colloid, 20 386-388 of PVC particles, 25 658-661, 661-663, 664-665... 

The enthalpy of formation of liquid and gaseous morpholine are —185.7 2.7 and —142.8 3.3 kJmol-1, respectively K. Pihlaja and P. Vainiotalo, unpublished results, cited by K. Pihlaja in Molecular Structure and Energetics Physical Measurements (Eds. J. F. Liebman and A. Greenberg), VCH, New York, 1987. From the same source we find V-methylmorpholine is ca 21 kJ mol1 less stable than its 1,3-counterpart parallelling the earlier conclusion that vic-diamines are less stable than file related g m-diamines. 

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