Highly stereoselective kinetic resolution of α-allenic alcohols: an enzymatic approach
作者:Wenhua Li、Zuming Lin、Long Chen、Xuechao Tian、Yan Wang、Sha-Hua Huang、Ran Hong
DOI:10.1016/j.tetlet.2015.12.098
日期:2016.2
A highly efficient lipase AK-catalyzed direct kinetic resolution of a variety of α-allenic alcohols was developed. With the complementary to previous studies, the current reaction system is effective on a broad range of substituents (R1) at C(1), such as alkyl, aryl, alkenyl, and alkynyl groups. The Jones–Burgess empirical model was modified to interpret the reversed selectivity during the acetylation
Catalytic Enantioselective Allenylation Reactions of Aldehydes with Tethered Bis(8-quinolinolato) (TBOx) Chromium Complex
作者:Guoyao Xia、Hisashi Yamamoto
DOI:10.1021/ja0679578
日期:2007.1.1
The utility of the new class of chiral ligand, tethered bis(8-quinolinol) (TBOxH), is further explored. Its chromiumcomplex, TBOxCr(III)Cl, effectively catalyzes the asymmetric allenylation reactions of various aldehydes at room temperature with high yields (up to 91%) and high enantioselectivities (up to 97% ee). The scope of the present method is shown to be wide, and this method represents an efficient
Opticallyactiveallenic and homopropargylic alcohols were obtained selectively by a chiral N-oxide-catalyzed reaction of aldehydes with propargyltrichlorosilane and allenyltrichlorosilane, prepared in situ from propargyl chloride.
Enzymatic Kinetic Resolution (EKR) of α-Allenols Enabled by a Commercially Available Immobilized Lipase
作者:Can Zhu、Tianyu Zhang
DOI:10.1055/s-0042-1751525
日期:——
practical EKR of α-allenols enabled by a commercially available immobilized lipase, Lipozyme TL-IM. The stereoselectivity factor (S-factor) of this kinetic resolution (KR) was investigated to reach up to >1000. The robust nature of the EKR strategy is reflected by a broad scope of α-allenol substrates with the excellent control of enantioselectivity. This method offers an alternative approach to access chiral