FORMATION OF DIHYDROTRIPHENODIOXAZINES AND DIHYDROISOTRIPHENODIOXAZINES BY ACIDIC TREATMENT OF SOME SUBSTITUTED 3H-PHENOXAZIN-3-ONES - ISOLATION AND CHARACTERIZATION - A NEW PERSPECTIVE IN THE CHEMISTRY OF OMMOCHROMES
FORMATION OF DIHYDROTRIPHENODIOXAZINES AND DIHYDROISOTRIPHENODIOXAZINES BY ACIDIC TREATMENT OF SOME SUBSTITUTED 3H-PHENOXAZIN-3-ONES - ISOLATION AND CHARACTERIZATION - A NEW PERSPECTIVE IN THE CHEMISTRY OF OMMOCHROMES
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DOI：
10.1021/jo00169a006
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发表时间：
1983-01-01
影响因子：
3.6
通讯作者：
SCHERILLO, G
中科院分区：
文献类型：
--
作者：
BOLOGNESE, A;PISCITELLI, C;SCHERILLO, G
结果L，9-二甲氧基-2-氨基-3-异烟肼-3-酮(4a)的甲醇-H_2SO_4溶液回流1h，分离出两个产物和15%未反应的4a。主要成分为羟基吩恶嗪酮5a，占40%。一种非常微小的黄色产物被显示为6a。化合物5a和6a经柱层析分离纯化，其结构经元素分析和波谱数据(IR、核磁共振、UV、MS)确证，产物为1，9-dicarbomethoxy-2-hydroxy-3H-phenoxazin-3-one.其~1H核磁共振谱(CDC13)显示出AMX芳香族谱型：C-7质子为三重态(7.35)，C-6质子(7.53)为二重态，C-8质子(8.07)为双重态，这是由于在较低的磁场下，由于接近于甲氧基的存在。C-4质子(6.52)为明显的单重态，甲氧基团为(3.90，3.80)单重态。质谱图(M~+·329)显示一个密集的峰，具有苯醌结构的特征，5，红外光谱与文献报道的酚恶唑酮类化合物的红外光谱一致。而5a在氯仿中的紫外光谱
Results When a solution of l, 9-dicarbomethoxy-2-amino-3/iphenoxazin-3-one (4a) in methanol-H2S04 was refluxed for 1 h, two products were isolated as well as 15% un-reacted 4a. The major compound (40%) was the hydroxyphenoxazinone 5a. A very minor, yellow product was shown to be 6a. These substances, 5a and 6a, were sep-arated and purified by chromatography and the structures established by elemental analyses and spectral data (IR, NMR, UV, MS).The product 5a was identified as 1, 9-dicarbomethoxy-2-hydroxy-3H-phenoxazin-3-one. Its 1H NMR (CDC13) spectrum showed an AMX aromatic pattern: the C-7 proton appeared as a triplet (7.35) and the C-6 proton (7.53) was a doublet, as was the C-8 proton (8.07), this last one at lower field due to the near presence of the carbomethoxy group. The C-4 proton (6.52) appeared as a clearly distinguishable singlet, and the carbomethoxy groups were separated singlets (3.90, 3.80). The mass spectrum (M+· 329) showed an intensive peak, character-istic of the quinone structure, 5 and the IR spectrum was in clear agreement with that of the reported phenoxazi-nones. 6 Whereas the UV spectrum of 5a in chloroform