Pd-Catalyzed Reactions of Allenylphosphonates and Related Allenes with Functionalized 2-Iodophenols, 2-Iodobenzoic Acid, and 2-Iodobenzyl Alcohol Leading to Functionalized Benzofurans, Isocoumarins, and Benzopyrans
作者:M. Phani Pavan、Manab Chakravarty、K. C. Kumara Swamy
DOI:10.1002/ejoc.200900865
日期:2009.12
(1H/31P NMR) in reactions by using functionalized iodophenols, essentially as single isomers. The synthetic potential of these products possessing an aldehyde functionality is demonstrated by isolating a compound with the skeleton of Obovaten and many other 2,3,5,7-tetrasubstituted benzofurans. From the reaction of 2-iodophenol and PdII(OAc)2/PAr3, isolation and structural characterization of the (hydroxy)aryl
烯基膦酸酯 (OCH2CMe2CH2O)P(O)CH=C=CRR' [R, R' = H (1a), R = H, R' = Me (1b), R = R' = 的区域选择性钯催化偶联反应Me (1c)] 和苯基丙二烯 PhCH=C=CR2 [R = H (2a), Me (2b)] 与官能化碘酚(在 PEG-400 中)、2-碘苯甲酸和 2-碘苯甲醇进行了研究。具有游离醛官能团的苯并呋喃在反应中通过使用官能化碘苯酚以高产率 (1H/31P NMR) 形成,基本上作为单一异构体。通过分离具有 Obovaten 和许多其他 2,3,5,7-四取代苯并呋喃骨架的化合物,证明了这些具有醛官能团的产品的合成潜力。从 2-碘苯酚和 PdII(OAc)2/PAr3 的反应,分离和结构表征 (羟基) 芳基氧化膦 (Ar)2P(O)(C6H4-2-OH) (Ar = Ph, 4-MeOC6H4) 表明 P-芳基到