Exploring Structural Diversity in Ligand Design: The Aminoindanol Case

Abstract

A series of enantiopure ligands based on the aminoindanol scaffold, but differing in regio-and stereochemistry has been synthesized. These ligands have been conveniently derivatized and their catalytic efficiency in different enantioselective reactions has been screened to determine privileged candidates with respect to regio-and stereochemistry for each considered process. The nature of the amino substituent has been optimized for specific applications and this has led to the development of an efficient method for the preparation of bulky bicyclic amines by reductive amination.

Enantioselective Conjugate Addition of Catalytically Generated Zinc Homoenolate

“…(1R, 2S)-L6 was purchased from Aldrich and used only for preparing racemic and scalemic L6 for nonlinear effect study. Additional chiral ligands L8, 20 L9, 21 L10, 20 L11, 22 L12, 23 L13, 24 , L14, 20 L15, 20 L16, 25 L17, 26 L18, 27 and L19 26 were prepared according to the literature procedure and used during the optimization study.…”

Enantioselective synthesis of α,α-difluoro-β-lactams using amino alcohol ligands

“…The ligand (L2) was synthesized following the procedure described in the literature. 29 General procedure for the enantioselective imino-Reformatsky reaction of ethyl bromodifluoroacetate Ethyl bromodifluoroacetate (2) (2.0 mmol, 0.26 mL) was added to a solution of the corresponding imine (1 mmol) and (1R,2S)-1-phenyl-2-(1-pyrrolidinyl)-propan-1-ol (L1) (1.0 mmol, 205 mg) in CH 2 Cl 2 (8 mL) at ambient temperature. Then, the mixture was cooled to 0 °C, and 1.0 M Et 2 Zn in hexane (3.5 mmol, 3.5 mL) was slowly added to the mixture at 0 °C.…”

Synthesis and Mechanistic Interrogation of Ginkgo biloba Chemical Space en route to (–)-Bilobalide

“…(+)-Indabox…….……………. (3aR,3a'R,8aS,8a'S)-2,2'-(propane-2,2-diyl)bis(3a,8a-dihydro-8H-indeno[1,2-d]oxazole) 101 2.) Mn(dpm) 3 ……….………………………………………….Tris(2,2,6,6-tetramethyl-3,5-heptanedionato)manganese(III) 102 3.)…”