Morpholino group

The weak leaving group ability of the morpholino group provided an excellent opportunity to measure a far greater range of substituent effects than those possible with the dC N3 adduct. From this effort, the reversibility of QM alkylation was observed to vary over many orders of magnitude by the mere presence of a single substituent attached... 

If the vinyleyclobutanone is substituted in the 3-position by a morpholino group, which can stabilize a cationic center, then C3 migrates instead of the carbonyl group on treatment with /Moluenesulfonic acid to give 3.70... 

BN) to the olefin, accompanied in some cases by the adduct-dimers 2 formed by dimerization of two IBN-olefin adduct radicals (Table l). Most olefins gave only moderate yields (20-49%) of the bisadducts 1 however when substituted by bulky tm-butylthio or morpholino groups, higher yields were obtained. The... 

Fluoroalkoxy tellurium chlorides react with N-trimethylsilylmorpholine in diethyl ether at 5° with preferential replacement of fluoroalkoxy groups. Only two morpholino groups can be introduced into the molecules, even when an excess of the amine is used1. 

The pyrrolidine ring in 79 has an envelope conformation and the morpholino groups in 77 and 83 as well as the piperidino groups in 78 possess a chair conformation. The cyclohexene moieties in 77 to 82 exist in half-chair conformations. 

In 77, N has maintained an sp3 pyramidal configuration rather than an sp2 planar configuration. The morpholino group is rotated out of the plane of the double bond by about 33°. In 83 the three morpholino groups are not equivalently bonded to the ethene moiety. The two C1—N distances with 1.398 and 1.415 A are significantly shorter than the C2—N3 distance of 1.442 A. This indicates conjugative delocalization of... 

The steric course of the nucleophilic substitution at a [n.l.0]bicycle was investigated by using the deuterated compound 437. The expulsion of the exo-morpholino group was favored by at least a ratio of 99 1 Depending on the nature of the nucleophile and... 

Selective reductive deamination of one of the morpholino groups of 4,4-dimorpholin-4-ylpyrazol-3-one 409 was achieved by treatment with sodium dithionite in aqueous ethanol. 4-Morpholin-4-ylpyrazol-3-one 410 was obtained in 80% yield (68M2157) (Scheme 114). 

Alkyl TPs, usually minor side products of the alkylation (yield 0.2-5%), are more abundant (yield 10-19%) in the reaction of 2-morpholino-7-oxo TP ammonium salts (e.g., 91b). The large morpholino group may be twisted out of the TP plain, while the smaller methylthio group (in 91a) is coplanar, and conjugation lowers the nucleophilicity of N-1. 

Lithium aluminum hydride in tetrahydrofuran reduces the pyridazine moiety of pyrido[3,4-pyridazine ring by electron-donating morpholino groups results in reduction of the pyridine part by sodium borohydride to give 8.119... 

If a large excess of Grignard reagent (4-20 equivalents) is used, the 8-morpholino group is also replaced by the alkyl group with formation of 4.62... 

Attempts to apply the azide-tetrazole isomerism to the synthesis of tetrazolo[l,5-a][l,3,5]triazines were published <88IZV491>. This equilibrium was found to be shifted generally to the ring opened azides (31), and the maximum amount of the tetrazole (32) of 15% was detected in DMSO-de at 20 °C in the case of = H, R = morpholino group. The same tetrazolo ring system was, however, found to be stable with 5-styryl and 7-thio substitution <87LA65> aminotetrazole (33) when reacted with cinnamoyl isothiocyanate alTorded the tetrazolotriazine-thione (34) most likely formed via cyclization of the intermediate thiourea. 

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