Thieno[2,3-d]Pyrimidin-4-Ones. Part 3.* Electrophilic Ipso-Substitution Reactions of Methyl and Methoxycarbonyl Groups
B. Zh. Elmuradov *
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
Kh. A. Bozorov
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
А. Zh. Kurbanbayeva
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
I. S. Ortikov
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
Kh. M. Bobakulov
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
N. D. Abdullayev
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
A. Yili2, H. A. Aisa
Key Laboratory of Xinjiang Indigenous Medicinal Plants Resource Utilization, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, 830011, China
Kh. М. Shakhidoyatov
Organic Synthesis Department, Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent 100170, Uzbekistan
*Author to whom correspondence should be addressed.
Abstract
Interactions of 5,6-dimethyl- (1), 3,5,6-trimethylthieno[2,3-d]pyrimidin-4(3H)-ones (2) and 2,3-dimethyl- (5-7), 2-methyl-3-methoxycarbonylthieno[2,3-d]dihydropyrrolo-, -tetrahydropyrido-, tetrahydroazepino[1,2-a]pyrimidin-4-ones (14-16) with nitrating mixture were investigated. For the first time it is shown, that in dependence on the presence of substituent in position 2 and 3 of pyrimidine and thiophene rings reaction goes in various directions; by electrophilic ipso-substitution of methyl groups at C-5 by nitro group, or its oxidation up to carboxyl groups with formation corresponding 5-carboxy derivatives. It is revealed, that at absence of the substituent in position 3 (compound 1) the electrophilic ipso-substitution of methyl group by nitro group with formation of 5-nitro derivative took place. It is found, that at interaction of compounds 2,5-7, 14-16 with nitrating mixture instead of substitution of methyl groups at C-2, goes in an unexpected direction, i.e. there are oxidation of methyl groups or electrophilic ipso-substitution of methoxycarbonyl groups in position 3 by nitro group.
Keywords: thieno[2,3-d]pyrimidin-4-ones, nitrating mixture, electrophilic ipso-substitution, oxidation, methyl groups