5-Methoxy-6H-l,2,4-triazines la-c, 5H-l,2,4-triazine-6-diethylcarboxamides 7a, b and 3,6diphenyl-l,2,4-triazine 4-oxide 10 were lithiated with lithium 2,2,6,6-tetramethylpiperidide and the formed lithio-1,2,4-triazines 2a -c, 8a, b, 1J, reacted with chlorotrimethylsilane and other reagents to give the bi-1,2,4triazines 3a -c, 4a, b, 12, 13. 6-Lithio-l,2,4-triazines 2a, b afforded 3a, b and 5-methoxy-l,2,4-triazine-6carbaldehydes 5a, b when reacted with N-formylpiperidine or ethyl formate. Treatment of the 3-aryl-5-methoxy-l,2,4-triazines la-c with four equivalents lithium 2,2,6,6tetramethylpiperidide (LiTMP) in tetrahydrofurane (THF) at -100 °C and reaction of the formed 6-lithio derivatives 2a -c with chlorotrimethylsilane by the equilibrium shift procedure (8) afforded unexpectedly not the 6-trimethylsilyl-l,2,4-triazines but the 5,5'-dimethoxy-6,6'-bi-l,2,4-triazines 3a -c and the l,6-dihydro-6,6'bi-l,2,4-triazines 4a, b. As described earlier (1), to shift the equilibrium i + LiTMP 2 + TMPH to the right side, getting the highest yield of 2, one has to use a three-to fourfold excess of LiTMP.
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