HPLC of Formula: C15H12O. Ishibashi, A; Kamihigashi, S; Iwai, Y; Sakaguchi, S in [Ishibashi, Azusa; Kamihigashi, Shun; Iwai, Yuuki; Sakaguchi, Satoshi] Kansai Univ, Fac Chem Mat & Bioengn, Dept Chem & Mat Engn, Suita, Osaka 5648680, Japan published (+/-)-trans-1,2-Cyclohexanediamine-Based Bis(NHC) Ligand for Cu-Catalyzed Asymmetric Conjugate Addition Reaction in 2019.0, Cited 107.0. The Name is Chalcone. Through research, I have a further understanding and discovery of 94-41-7.
Bis(NHC) ligand precursors, L1, based on trans-1,2-diaminocyclohexane were designed and synthesized. To introduce chirality at the hydroxyamide side arm on the NHC of L1, a chiral beta-amino alcohol, such as enantiopure leucinol, was used. Cu-catalyzed asymmetric conjugate addition reactions of cyclic and acyclic enones with Et2Zn were selected to evaluate the performance of L1 as a chiral ligand. For the reaction of cyclic enone, a combination of [bis(trimethylsilyl)acetylene]-(hexafluoroacetylacetonato)copper(I) (Cu(hfacac)(btmsa)) with a (+/-)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand precursor, (rac; S,S)-L1, which was prepared from (S)-leucinol, was the most effective. Thus, treating 2-cyclohexen-1-one (3) with Et2Zn in the presence of catalytic amounts of Cu(hfacac)(btmsa) and (rac; S,S)-L1 afforded (R)-3-ethylcyclohexanone ((R)-4) with 97% ee. Similarly, use of (rac; R,R)-L1, which was prepared from (R)-leucinol, produced (S)-4 with 97% ee. Conversely, for the asymmetric 1,4-addition reaction of the acyclic enone, optically pure (-)-trans-1,2-cyclohexanediamine-based bis(NHC) ligand precursor, (R,R; S,S)-L1, worked efficiently. For example, 3-nonen-2-one (5) was reacted with Et 2 Zn using the CuOAc/(R,R; S,S)-L1 catalytic system to afford (R)-4-ethylnonan-2-one ((R)-6) with 90% ee. Furthermore, initially changing the counterion of the Cu precatalyst between an OAc and a ClO4 ligand on the metal reversed the facial selectivity of the approach of the substrates. Thus, the conjugate addition reaction of 5 with Et2Zn using the Cu(ClO4)(2)/(R,R; S,S)-L1 catalytic system, afforded (S)-6 with 75% ee.
HPLC of Formula: C15H12O. Welcome to talk about 94-41-7, If you have any questions, you can contact Ishibashi, A; Kamihigashi, S; Iwai, Y; Sakaguchi, S or send Email.
Reference:
Thiazolidine – Wikipedia,
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