90905-31-0Relevant articles and documents
Synthesis of Soai Type 2-Arylpyrimidine-5-carbaldehydes through Desulfurative Cross-Coupling with Arylboronic Acids
Maltsev, Oleg V.,Rausch, Rodger,Quan, Zheng-Jun,Hintermann, Lukas
supporting information, p. 7426 - 7432 (2016/02/20)
A two-step synthesis of 2-arylpyrimidine-5-carbaldehydes, which are of relevance as substrates for Soai's asymmetric autocatalysis, was realized by exploiting a hidden threefold symmetry in the target core structure. Condensation of Arnold's C 3-symmetric vinamidinium cation with S-methylisothiouronium sulfate provides 2-methylsulfanyl-pyrimidine-5-carbaldehyde; introduction of aryl groups at C-2 of the latter was accomplished by a Liebeskind-Srogl palladium-catalyzed desulfurative (de-methylsulfanylative) coupling with aryl boronic acids to obtain the target compounds 1 (14 examples, 60-95 % yield). 2-Arylpyrimidine-5-carbaldehydes, which are of relevance as substrates in Soai's asymmetric autocatalysis, are prepared through Liebeskind-Srogl coupling of aryl boronic acids with 2-methylthiopyrimidine-5-carbaldehyde; the latter is obtained in a hydrolytic condensation of two symmetric amidinium salts.
DIRECT SYNTHESIS OF 2-SUBSTITUTED 5-FORMYLPYRIMIDINES AND RING TRANSFORMATION OF THEIR PHENYLHYDRAZONES INTO 4-FORMYL-1-PHENYLPYRAZOLE
Takagi, Kaname,Bajnati, Abdelilah,Hubert-Habart, Michel
, p. 1105 - 1109 (2007/10/02)
Triformylmethane (1) reacted with benzamidine, guanidine and S-methylisothiourea to give 2-substituted 5-formylpyrimidines (2a-c), whose phenylhydrazones (3a-c) readily underwent ring transformation into 4-formyl-1-phenylpyrazole (4) on heating in acidic methanol.