1448251-14-6Relevant articles and documents
Asymmetric Hydroesterification of Diarylmethyl Carbinols
Tian, Duanshuai,Xu, Ronghua,Zhu, Jinbin,Huang, Jianxun,Dong, Wei,Claverie, Jerome,Tang, Wenjun
, p. 6305 - 6309 (2021/02/09)
An efficient asymmetric hydroesterfication of diarylmethyl carbinols is developed for the first time with a Pd-WingPhos catalyst, resulting in a series of chiral 4-aryl-3,4-dihydrocoumarins in excellent enantioselectivities and good yields. The method features mild reaction conditions, a broad substrate scope, use of easily accessible starting materials, and low palladium loadings. A plausible stereochemical model is also proposed with the Pd-WingPhos catalyst. This method has enabled a 4-step asymmetric synthesis of (R)-tolterodine from readily available starting materials.
OH-directed alkynylation of 2-vinylphenols with ethynyl benziodoxolones: A fast access to terminal 1,3-enynes
Finkbeiner, Peter,Kloeckner, Ulrich,Nachtsheim, Boris J.
supporting information, p. 4949 - 4952 (2015/04/14)
The first direct alkynylation of 2-vinylphenols was developed. The rationally optimized hypervalent iodine reagent TIPS-EBX in combination with [(CpRhCl2)2] as a C-H-activating transition metal catalyst enables the construction of a variety of highly substituted 1,3-enynes in high yields of up to 98 %. This novel C-H activation method shows excellent chemoselectivity and exclusive (Z)-stereoselectivity, and it is also remarkably mild and tolerates a variety of functional groups. Furthermore, synthetic modifications of the resulting 1,3-enynes were demonstrated. To our knowledge, this is the first example for an OH-directed C-H alkynylation with hypervalent iodine reagents.
Palladium(II)-catalyzed direct carboxylation of alkenyl C-H bonds with CO2
Sasano, Kota,Takaya, Jun,Iwasawa, Nobuharu
, p. 10954 - 10957 (2013/08/23)
Pd-catalyzed direct carboxylation of alkenyl C-H bonds with carbon dioxide was realized for the first time. Treatment of 2-hydroxystyrenes and a catalytic amount of Pd(OAc)2 with Cs2CO3 under atmospheric pressure of CO2 afforded corresponding coumarins in good yield. Furthermore, isolation of the key alkenylpalladium intermediate via C-H bond cleavage was achieved. The reaction was proposed to undergo reversible nucleophilic addition of the alkenylpalladium intermediate to CO2.
