6-Nitro- 2,3,4-trimethoxy

The synthesis of 3-H-oxazol-2-ones was described by Nam et al. [69]. The substituted benzoin 89 was formed from the coupling of 3,4,5-trimethoxy-benzaldehyde 18 with 3-nitro-4-methoxybenzaldehyde, Scheme 22. Reaction with PMB-isocyanate and subsequent cyclization gave the protected oxazolone derivative 90. The PMB group was removed by reflux in TFA and reduction of the nitro-group was performed using Zn to give the combretoxazolone-aniline 91. 

Neben den bereits beschriebenen Difluor-azoxybenzolen (Bd.X/3, S.761) konnte auch 5-Nitro-l,2,3-trimethoxy-benzol in guten Ausbeuten zum 3,3, 4,4, 5,5 -Hexamethoxy-az-oxybenzol umgesetzt werden. Mit Zink und Calciumchlorid in waBrigem Methanol betragt die Ausbeute 82% mit Zink, Ammoniumchlorid und Salpetersaure entsteht ein Komplex aus dimerem 5-Nitroso-l,2,3-trimethoxy-benzol mit Zinkchlorid1. 

Auf analoge Weise erhalt man 2-Nitro-l,3,5-trimethoxy-benzol [Schmp. 151° (Methanol)] in 92%iger Ausbeute. 

Dimethoxy-2-(3-nitro-1,2,4-triazol-1 -yl)benzene and 1,1,4-trimethoxy-4-(3-nitro-l,2,4-triazol-l-yl)cyclohexane-2,5-diene have been prepared by indirect electrochemical method [598],... 

Hydroxy-ethoxy)-5-methoxy-1 -nitro- E16d, 288/335 (H -> N02) 5-(2-Hydroxy-ethoxy)-2-methoxy-l-nitro- El6d, 288/335 (H - N02) 2-Nitro-l,3,5-trimethoxy- E16d, 285 (Nitrierung)... 

Acetophenon a-Diazo-2,4,5-trimethoxy- E6b/1, 76 (Ar-COOH + S02C12/CH2N2) Acrylsaure 3-Anilino-2-nitro- -ethylester E15/2, 1369 [02N-CH2 COOR + R-NH2/ HC(OR)3]... 

Acetaldehyd 3,4,5-Trimethoxy-phenyl- -oxim X/4, 155 Benzol 1,4-Dimethoxy-2-(2-nitro-propyl)- E16d, 225 (En-Red.) Bicyclo 3.2.l octan 2,4-Dioxo-3-nitro-1,8,8-trimethyl- X/l, 15... 

Propan 2-Nitro-l-nitroso-l-(2,4,5-trimethoxy-phenyl)- (dimer) X/l, 74... 

The condensation of 2-bromo-5-methoxyphenylacetic acid with 2-nitro-3 4-dimethoxybenzaldehyde followed by reduction and cyclization by Pschorr s method affords 3 4 5-trimethoxy-8-bromophenan-threne-9-carboxylic acid [vm] in 10 per cent, overall yield. Debromina-tion of this followed by sodium amalgam reduction resulted in the 9 10-dihydro-derivative [ix], which was converted by the Curtius degradation to 3 4 5-trimethoxy-9-amino-9 10-dihydrophenanthrene... 

Nitro- -phenylimin 607 -oxim 25, 251, 537, 669f. -l-(bzw.-2)-phenyl-athylimin 227, 230 -l-phenyl-butyl-(3)-imin 228 -phenylhydrazon 242 -phenylimin 62, 228, 230, 670, 689, 709 -2,3,4-trimethoxy-phenyIimin 227 Vinyl- 57... 

Nitro-l, 1, l-trimethoxy-ethanls 79% 2-Chlor-2-nitro-l J.I-triethoxy-ethan75,7S 34%... 

The dinitrostyrene approach has also been applied to the preparation of 5,6,7-trimethoxyindole by reductive cyclization of 2-nitro-3,4,5-trimethoxy-) -nitrostyrene, obtained by the nitration of 3,4,5-trimethoxy-i -nitrostyrene in Ac O with fuming... 

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