2-nitro-5,6,7,8-tetrahydro

H-Azirin 2-(2,4-Dinitro-phenyl)-3-methyl- E16c, 323 (aus N-Sulfonyloxy-amidinen) lH-U-Benzodiazcpin 2,5-Dioxo-7-nitro-2,3,4,5-tetrahydro- E16d, 287 (Nitrierung)... 

It has been found that the simplest method of preparing 5-nitro-tetrahydro-l,3-oxazine derivatives consists in warming 2-alkyl-2-nitropropane-l,3-diol with formaldehyde and ammonia or primary amines ... 

Jltm Values in 3-Alkyl-5-methyu5-nitro-tetrahydro-1,3-oxazines266... 

A number of diastereoisomeric pairs of quaternary salts of 5-nitro-tetrahydro-l,3-oxazine derivatives (11a and lib) were prepared by the action of n-alkyl bromides or iodides on 5-nitrotetrahydro-1,3-oxazines.61 The products contained at the 3-equatorial position the n-alkyl derived from the alkyl bromide (or iodide), 6a and 6b [Eqs. (4) and (5)]. 

Investigations of the conformational analysis of 5-alkyl-5-nitro-tetrahydro-l,3-oxazines by dipole moments1 have been extended to derivatives with various substituents in positions 3 and 5.281-282 They... 

Oxazin 5-(4-Chlor-benzyl)-2-ethyl-5-nitro-tetrahydro- E14a/2, 711 (l,3-Diol/CH20/R-NH2)... 

Primary nitroparaffins react with two moles of formaldehyde and two moles of amines to yield 2-nitro-l,3-propanediamines. With excess formaldehyde, Mannich bases from primary nitroparaffins and primary amines can react further to give nitro-substituted cycHc derivatives, such as tetrahydro-l,3-oxa2iaes or hexahydropyrimidines (38,39). Pyrolysis of salts of Mannich bases, particularly of the boron trifluoride complex (40), yields nitro olefins by loss of the amine moiety. Closely related to the Mannich reaction is the formation of sodium 2-nitrobutane-1-sulfonate [76794-27-9] by warming 1-nitropropane with formaldehyde and sodium sulfite (41). 

Carbazole, 2-hydroxy-reactions with citral, 4, 235 Carbazole, 2-hydroxy-9-methyl-synthesis, 4, 294 Carbazole, N-hydroxymethyl-as metabolite of carbazole, 1, 230 Carbazole, N-isopropyl-PE spectroscopy, 4, 190 Carbazole, A7-methyl- N NMR, 4, 175 X-ray spectroscopy, 4, 163 Carbazole, 1-nitro-synthesis, 4, 282 Carbazole, tetrahydro-dehydrogenation, 4, 282, 312 synthesis, 4, 107, 337, 353 Carbazole, 1,2,3,4-tetrahydro-reduction, 4, 255, 256 synthesis, 4, 312, 325, 352 Carbazole, 1,2,3,4-tetrahydro-1 -oxo-synthesis, 4, 337 Carbazole, 9-trifluoroacetyl-synthesis, 4, 218 Carbazole, vinyl-polymers, 1, 275, 301 Carbazole, 9-vinyl-copolymer... 

H-1,2-Oxazine, 3,6-dihydro-6-(2-pyridyl)-mass spectra, 2, 529 2H-1,2-Oxazine, tetrahydro-synthesis, 2, 92 4H-l,2-Oxazine, 5,6-dihydro-pyrolysis, 3, 999 synthesis, 3, 1017 tautomerism, 3, 999 4H-1,2-Oxazine, 5,6-dihydro-3-methyl-metallation, 1, 484 4H-l,2-Oxazine, 5,6-dihydro-3-nitro-reactions, 3, 1000 6H-l,2-Oxazine, 3,5-diphenyl-stability, 3, 997 synthesis, 3, 1014... 

Quinoline, 4-methyl-5,6,7,8-tetrahydro-synthesis, 2, 471 Quinoline, 2-methylthio-3-nitro-3-substituted... 

Selenophene, 2-methylmercapto-conformation, 4, 944 Selenophene, 2-nitro-mercuration, 4, 946 Selenophene, 2-phenyl-irradiation, 4, 42, 946 mass spectra, 4, 942 Selenophene, 3-phenyl-mass spectra, 4, 942 Selenophene, tetrachloro-applications, 4, 971 reactions, 4, 955 synthesis, 4, 963 Selenophene, tetrahydro-conformation, 4, 34, 944 IR spectra, 4, 942 mass spectra, 4, 24, 943 molecular structure, 4, 938 NMR, 4, 10, 13 reactions, 4, 88, 958 ring strain, 4, 28 synthesis, 4, 118, 962, 968 Selenophene, tetraphenyl-synthesis, 4, 118, 962, 964 Selenophene, 2-thienyl-... 

By a modified Bischler-Napieralsky reaction, 6 -nitrophenylaceto-jS-3 4-methylenedioxyphenylethylamide, resulting from the condensation of -3 4-methylenedioxyphenylethylamine with 2-nitrophenylacetyl chloride, was converted into 6 nitro-l-benzyl-6 7-methylenedioxy-3 4-dihydroisoquinoline. The methiodide of the latter was reduced with zinc and hydrochloric acid to 6 -amino-l-benzyl-2-methyl-6 7-methylenedioxy-1 2 3 4-tetrahydro/soquinoline dihydrochloride, which by the Pschorr ring-closure reaction, produced dZ-roemerine (IV, p. 317), m.p. 85-7°. By treatment in succession with d- and Z-tartaric acids, the dZ-base was resolved into Z- and tZ-forms. Synthetic Z-roemerine is dimorphic, m.p. 85-7° and 102°, and has [aju — 79-9° (EtOH), these constants being in good agreement with those of the natural base. 

Cyclocondensation of 2-(nitromethylene)perhydropyrimidine (379) and dimethyl acetylenedicarboxylate yielded a mixture of 9-nitro-l,2,3,4-tetrahydro-6-oxo-6//-pyrido[l,2-n]pyrimidin-8-carboxylate 380 and a pyr-rolo[l,2-n]pyrimidine-7-ylideneacetate 381 (93BCJ2118). Their ratio... 

One of the most extensively investigated groups of 1,3-oxazine derivatives is the 5-nitro derivatives of tetrahydro-l,3-oxazine. They were first prepared from 1-nitropropane, aqueous formaldehyde, and ammonia by Hirst et and independently by Senkus from other primary nitroparaffins, formaldehyde, and primary amines. Numerous compounds of the general formula (6) were later prepared from primary nitroparaffins. " ... 

R = Ar) and cyclized tricyclic compound 240 (R = Ar) was obtained when 2-bromoacetophenones were reacted with 8-hydroxyquinolin-2(l//)-one under the above conditions. Presence of a 4-methoxy substituent shifted the equilibrium to the ring-opened product 241 (R = 4-MeOPh), while that of 4-nitro group gave only cyclized product 240 (R = N02). Similarly, mixtures of ring-opened and 2,3,6,7-tetrahydro-5//-pyrido[l,2,3- /e]-l,4-benzoxazin-5-one derivatives were formed in the reaction of 8-hydroxy-l,2,3,4-tetrahydroquinolin-2-one and halomethyl ketones (00HCA349). 

A solution of N-(2-aminobenzvl)-1-phenyl-2-metKylaminoethanol-1 was prepared by the reaction of a-bromo-acetophenone and (2-nitrobenzyl)methylamine, followed by hydrogenation of the nitro group by means of nickei on diatomaceous earth at room temperature and reduction of the CO group by means of sodium borohydride. The intermediate thus produced was dissolved in 100 ml of methylene chloride and introduced dropwise into 125 ml of sulfuric acid at 10° to 15°C. After a short standing, the reaction mixture was poured onto ice and rendered alkaline by means of a sodium hydroxide solution. Dy extraction with ether, there was obtained 1,2,3,4-tetrahydro-2-methyl-4-phenyl-8-amino-iso-quinoline. The base is reacted with maleic acid to give the maleate melting point of the maleate 199° to 201°C (from ethanol). 

Chemical Name 1,2,3,4-Tetrahydro-2-[ [(1 -methylethyDamino] methyl] -7-nitro-6-quino-linem ethanol... 

Double deprotonation of tetrahydro-2-(2-nilroethoxy)-2//-pyran (8) and reaction with electrophiles provides a variety of substituted and functionalized nitroaldols1 Reaction with aldehydes affords 2-nitro-l,3-alkanediols 9 in 44 90% yield and high diastereoselectivities. From analogy of their II-NMR spectra and comparison with known compounds, the (R, R ) relative configuration is likely15. 

A similar study has been reported using l-nitro-2-[(S,S)-2-phenylpropylsulfinyl]-l-cyclo-hexene and zinc enolates of tetrahydro-2(3//)-pyridinones34. 

Propionic acid, 2-iodo-3-nitro-, ethyl ester [Propanoic acid, 2-iodo-3-mtro-, ethyl ester], 65 2//-Pyran, 3,4-dihydro-, 51 2//-PYR AN-2-ONE, 49 2H Pyran 2-one, 5 bromo 5,6-dihydro, 50 27/-PYRAN-2-ONE, 5,6 DIHYDRO-, 49 PYRIDINE, 2,3,4,5 TETRAHYDRO, 118 Pyridines, -substituted, 34 a Pyrone-6-carboxyhc acid [2H Pyran-6-Larboxyhc acid 2-oxo ], 51 Pyrroles, 34... 

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