28937-18-0Relevant academic research and scientific papers
Rhodium-Catalyzed Desymmetric Arylation of γ,γ-Disubsituted Cyclohexadienones: Asymmetric Synthesis of Chiral All-Carbon Quaternary Centers
Qiao, Yu,Bai, Shiming,Wu, Xiao-Feng,Yang, Ying,Meng, He,Ming, Jialin
, p. 1556 - 1560 (2022/02/23)
The desymmetric arylation of prochiral cyclohexadienones with ArZnCl in the presence of an (R)-segphos-rhodium catalyst gave high yields of the corresponding cyclohexenones, which contain a chiral arylated carbon center at the β-position and a chiral all-carbon quaternary center at the γ-position, with high diastereo- and enantioselectivities. This catalytic system was also applied to the arylation of spirocarbocyclic cyclohexadienones and afforded the corresponding cyclohexenones bearing a chiral spiro quaternary carbon with high dr and ee.
Strong and Confined Acids Control Five Stereogenic Centers in Catalytic Asymmetric Diels–Alder Reactions of Cyclohexadienones with Cyclopentadiene
Bistoni, Giovanni,Das, Sayantani,De, Chandra Kanta,Ghosh, Santanu,Leutzsch, Markus,List, Benjamin,Neese, Frank,Yepes, Diana
, p. 12347 - 12351 (2020/03/23)
We describe a highly enantioselective Diels–Alder reaction of cross-conjugated cyclohexadienones with cyclopentadiene, in which five stereocenters are effectively controlled by a strongly acidic and confined imidodiphosphorimidate catalyst. Our approach provides tricyclic products in excellent stereoselectivity. We also report methods to convert the obtained products into useful intermediates and a computational study that aids in gaining deeper insight into the reaction mechanism and origin of stereoselectivity.
Nickel-Catalyzed Desymmetric Hydrogenation of Cyclohexadienones: An Efficient Approach to All-Carbon Quaternary Stereocenters
You, Cai,Li, Xiuxiu,Gong, Quan,Wen, Jialin,Zhang, Xumu
, p. 14560 - 14564 (2019/10/11)
Nickel-catalyzed desymmetric hydrogenation has been achieved. With the Ni(OTf)2/(S,S)-Ph-BPE system, a series of ?,?-disubstituted cyclohexadienones were transformed to the corresponding cyclohexenones with a chiral all-carbon quaternary center at the γposition in high yields (92-98%) and excellent enantioselectivities (92%-99% ee). This catalytic system can also tolerate the desymmetric reaction of spirocarbocyclic cyclohexadienones to produce the corresponding cyclohexenones bearing a chiral spiro quaternary carbon with high yields (94%-98%) and ee values (96%-99% ee). Furthermore, this methodology provides an efficient and concise synthetic route to the intermediate of natural products cannabispirenones A and B.
Asymmetric Synthesis of Remote Quaternary Centers by Copper-Catalyzed Desymmetrization: An Enantioselective Total Synthesis of (+)-Mesembrine
Bokka, Apparao,Mao, James X.,Hartung, John,Martinez, Steven R.,Simanis, Justin A.,Nam, Kwangho,Jeon, Junha,Shen, Xiaoqiang
, p. 5158 - 5162 (2018/09/13)
Catalytic asymmetric syntheses of remote quaternary stereocenters have been developed by copper-catalyzed 1,4-hydrosilylation of ?,?-disubstituted cyclohexadienones. A variety of cyclohexenones have been synthesized in good yield and excellent enantioselectivity. Versatile 2-silyloxy diene intermediates bearing ?,?-disubstituted all carbon stereogenic centers can be isolated from the mild reaction conditions. The utility of this strategy is exemplified in a catalytic asymmetric total synthesis of (+)-mesembrine.
Asymmetric Induction at Remote Quaternary Centers of Cyclohexadienones by Rhodium-Catalyzed Conjugate Hydrosilylation
Naganawa, Yuki,Kawagishi, Mayu,Ito, Jun-Ichi,Nishiyama, Hisao
, p. 6873 - 6876 (2016/06/13)
The enantioselective desymmetrizing conjugate hydrosilylation of prochiral differently γ,γ-disubstituted cyclohexadienone derivatives 2 to furnish the corresponding cyclohexenones 4 with a remote chiral all-carbon quaternary center at the γ position is de
SOLID STATE PHOTOCHEMISTRY OF 2,5-CYCLOHEXADIENONES
Matsuura, Teruo,Meng, Ji-Ben,Ito, Yoshikatsu,Irie, Miwako,Fukuyama, Keiichi
, p. 2451 - 2456 (2007/10/02)
Santonin, a 2,5-cyclohexadienone, is known to undergo photorearrangement to lumisantonin in solution but to a cyclopentadienone in the solid state in accordance with the topochemical principle of a minimum of atomic movement in crystal lattice.In contrast
