Triazolo[4,5-d]pyrimidines. IX. Reactions of 5-chloro- and 5-(methylsulfonyl)-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidines with C-nucleophiles.
作者:Ken-ichi TANJI、Katsuhisa YAMAMOTO、Takeo HIGASHINO
DOI:10.1248/cpb.37.1731
日期:——
The nuclephilic substitution of 5-(methylsulfonyl)-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine (2) with potassium cyanide proceeded smoothly to give 3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine-5-carbonitrile (6), but the same reaction did not take place in the case of 5-chloro-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine (1).Compounds 1 and 2 reacted with ethyl cyanoacetate in the presence of sodium hydride in tetrahydrofuran, giving ethyl α-cyano-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine-5-acetate (7). When acetote was used as a ketone, it added across the C7, N6-double bond, giving 7-acetonyl-5-chloro-6, 7-dihydro- (8a) and 7-acetonyl-6, 7-dihydro-5-(methylsulfonyl)-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidines (8b), respectively, although the yields were low.The reaction of 1 with Grignard reagents resulted in the formation of addition products such as 7-alkylated 5-chloro-6, 7-dihydro-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidines (9a-e). The substitution of the methylsulfonyl group of 2 with Grignard reagents proceeded to give the corresponding 5-alkylated 3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidines (11a-e).
5- (甲磺酰基) -3-苯基-3H-1, 2, 3-三唑并[4, 5-d]嘧啶 (2) 与氰化钾的亲核取代反应顺利进行,得到 3-苯基-3H-1, 2, 3-三唑并[4, 5-d]嘧啶-5-甲腈 (6)、2,3-三唑并[4,5-d]嘧啶-5-甲腈(6),但 5-氯-3-苯基-3H-1,2,3-三唑并[4,5-d]嘧啶(1)没有发生同样的反应。在氢化钠存在下,化合物 1 和 2 与氰基乙酸乙酯在四氢呋喃中发生反应,生成 α-氰基-3-苯基-3H-1,2,3-三唑并[4,5-d]嘧啶-5-乙酸乙酯(7)。当乙酰酮用作酮时,它穿过 C7,N6-双键,分别得到 7-丙酮基-5-氯-6,7-二氢-(8a)和 7-丙酮基-6,7-二氢-5-(甲磺酰基)-3-苯基-3H-1,2,3-三唑并[4,5-d]嘧啶(8b),但产率较低。1 与格氏试剂反应会生成加成产物,如 7-烷基化的 5-氯-6,7-二氢-3-苯基-3H-1,2,3-三唑并[4,5-d]嘧啶(9a-e)。用格氏试剂取代 2 的甲磺酰基,可得到相应的 5-烷基化 3-苯基-3H-1,2,3-三唑并[4,5-d]嘧啶(11a-e)。