73112-02-4Relevant academic research and scientific papers
Carbon-carbon bond cleavage of α-hydroxybenzylheteroarenes catalyzed by cyanide ion: Retro-benzoin condensation affords ketones and heteroarenes and benzyl migration affords benzylheteroarenes and arenecarbaldehydes
Suzuki, Yumiko,Takemura, Yuki,Iwamoto, Ken-Ichi,Higashino, Takeo,Miyashita, Akira
, p. 199 - 206 (2007/10/03)
4-(α-Benzylα-hydroxybenzyl)quinazoline (4a) underwent retro-benzoin condensation catalyzed by cyanide ion to give deoxybenzoin (2a) and quinazoline (5a). Similarly, several nitrogen-containing heteroarenes (4, 9, 12, 16-19) having an α-hydroxybenzyl group at the α-position of the nitrogen underwent retro-benzoin type condensation to afford kelones (2) and heteroarenes (5). However, similar reaction of pyrazolopyrimidines (13, 14, 15) having an α-benzyl-α-hydroxybelzyl group resulted in benzyl migration, giving benzylpyrazolopyrimidines (8) and arenecarbaldehydes (3). Tetrabutylammonium cyanide (11, Bu4NCN) was a more effective cyanide ion donor than KCN (10). The retro-benzoin condensation was applied to the synthesis of 2-substituted quinazolines (38) from 2-chloro-4- aroylquinazolines (34), using the aroyl group as a protecting and electron- withdrawing group.
Triazolo[4,5-d]pyrimidines. XII. Reactions of 6-benzoyl-6,7-dihydro-3-phenyl-3H-1,2,3-triazolo-[4,5-d]pyrimidines (triazolopyrimidine Reissert compounds) with acid, base, and electrophile
Tanji,Sato,Kanamura,Iijima,Miyashita,Higashino
, p. 513 - 517 (2007/10/02)
In the treatment of 6-benzoyl-6,7-dihydro-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidine-7-car bonitrile (1, triazolopyrimidine Reissert compound) and 6-benzoyl-6,7-dihydro-5-methyl-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimid ine-7-carbonitrile (2,5-methyltriazolopyrimidine Reissert compound) with an acid, the ring fission of the pyrimidine ring proceeded to give the triazole derivatives (3-7). Alkaline hydrolysis of 2 and 1 gave 5-methyl-3-phenyl- (10) and 3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidines (9), respectively. The anions, generated from 1 and 2 with sodium hydride (NaH), underwent aromatization to give the 3H-1,2,3-triazolo[4,5-d]pyrimidine-7-carbonitriles (12 and 14). Compounds 1 and 2 reacted with arylaldehydes in the presence of NaH to give corresponding 3H-1,2,3-triazolo[4,5-d]pyrimidin-7-ylmethyl benzoates (15 and 17).
Triazolo[4,5-d]pyrimidines. X. Halogen-metal exchange reaction of 7-halo-3-phenyl-3H-1,2,3-triazolo[4,5-d)pyrimidines with butyllithium
Tanji,Kato,Higashino
, p. 2793 - 2796 (2007/10/02)
The amino group at the 7-position on the 3H-1,2,3-triazolo[4,5-d]pyrimidine ring was converted into halogen atoms by treatment with isopentyl nitrite in halomethanes, in satisfactory yields. The halogen-metal exchange reaction between 7-iodo-3-phenyl-3H-1
Triazolo[4,5-d]pyrimidines. XI. Halogen-metal exchange reaction of 5-halo-3H-1,2,3-triazolo-[4,5-d]pyrimidines with butyllithium
Tanji,Kato,Higashino
, p. 3037 - 3040 (2007/10/02)
The amino group at the 5-position on the 3H-1,2,3-triazolo[4,5-d]pyrimidine (triazolopyrimidine) ring was converted into a halogen atom by treatment with isopentyl nitrite in halomethanes in satisfactory yields. The 5-halotriazolopyrimidines not having a
