157563-40-1

Usage

Chirality

Chiral compound with the (aR)designation indicating specific spatial arrangement of atoms

Application

Used as a precursor in organic synthesis, especially in pharmaceutical and fine chemical production

Functional Groups

Bromo and benzyloxy functional groups

Reactivity

Can be utilized as a reagent in certain chemical reactions

Handling

Requires careful handling and storage precautions due to potential hazards

Upstream product

• 557-20-0 diethylzinc 
• 6630-33-7 ortho-bromobenzaldehyde 

Downstream Products

• 157563-45-6 2-((R)-1-Hydroxy-propyl)-benzaldehyde 

Relevant academic research and scientific papers

Binaphthyl-based chiral ligands: Design, synthesis and evaluation of their performance in enantioselective addition of diethylzinc to aromatic aldehydes

The design strategy and the performance of binaphthyl-based chiral ligands were evaluated with computation and enantioselective addition of diethylzinc to aromatic aldehydes. Under optimized conditions, enantioselective addition of diethylzinc to aromatic aldehydes provided the desired optically active secondary alcohols in high isolated yields (up to 91%) and excellent enantiomeric excesses (up to 98% ee).

Isosterically designed chiral catalysts: Rationale, optimization and their application in enantioselective nucleophilic addition to aldehydes

Proline-based N,N′-dioxide ligands were designed on the basis of isosteric approach, and were successfully applied in enantioselective nucleophilic addition to aldehydes. In the presence of 10 mol% of chiral ligand 1b, enantioselective addition of diethylzinc to aldehydes provided the corresponding secondary alcohols in up to 90% isolated yield and up to 99% ee. Similarly, using 3e as chiral ligand, enantioselective arylation and alkynylation of aldehydes also proceeded readily, leading to the desired chiral alcohols in up to 92% isolated yield at 99% ee and 80% isolated yields and up to 84% ee, respectively. The current work would shed light on expanding the structure diversity in the design of chiral ligands and chiral catalysts.

Design of a Chiral Ionic Liquid System for the Enantioselective Addition of Diethylzinc to Aldehydes

An important contribution to the field of asymmetric catalysis is described in this work, as it merges the search for new ligands that can provide high performance in asymmetric catalysis with the extremely important and increasing need for sustainability. New chiral ionic liquids have been synthesised from the amino acid l-cysteine by straightforward routes. With these ligands, we have developed a chiral ionic system that includes chiral ionic liquids and their immobilisation in ionic solvents to provide a chiral supramolecular structure. These new catalytic systems were used in the enantioselective addition of alkylzinc to aldehydes and proved to be very efficient, capable of providing chiral secondary alcohols in excellent enantiomeric excesses and yields. This system also enabled the recycling of the ionic media and the ionic ligand, taking into account green chemistry considerations.

New atropisomeric amino alcohol ligands for enantioselective addition of diethylzinc to aldehydes

Efficient synthesis of several new atropisomeric amino alcohols having 1-phenyl-1H-pyrrole skeleton are reported. Steric arrangements of the products were confirmed by a single-crystal X-ray measurement. The consequences of the size of the N-substituents

Synthesis of quinazolinone-based aziridine diols as chiral ligands: Dual stereoselectivity in the asymmetric ethylation of aryl aldehydes Dedicated to Professor Dr. Metin Balci on the occasion of his retirement

A new class of quinazoline-based enantiomerically pure aziridine diols 4a-d were prepared from the aziridination of mesityl oxide 3 with in situ generated 3-acetoxyaminoquinazolinone (S)-2b followed by NaBH4 reduction. Aziridine diols 4a-d were purified by means of column chromatography on silica gel and their stereochemistries were assigned by X-ray crystallography and NMR analysis. These aziridine diols 4 were evaluated as chiral ligands in the asymmetric addition of diethylzinc to aryl aldehydes, and ligand (S,R,R)-4a yielded (R)-1-phenylpropanol derivatives with up to 92% ee, while the diastereomer (S,S,R)-4c gave the opposite enantiomers (S)-1-phenylpropanol derivatives with up to 86% ee. The results demonstrate that switching the configuration of the aziridine alcohol moiety in ligand gives a remarkable reversal of enantioselectivity in the asymmetric addition of diethylzinc to aryl aldehydes.

Enantioselective addition of diethylzinc to aldehydes catalyzed by diastereomeric 1,4-amino alcohols with o-xylylene skeleton

Two diastereomeric 1,4-amino alcohols with o-xylylene structure (S,R)-2 and (S,S)-3, synthesized from chiral 1,4-diol (S,S)-1, were utilized as chiral ligands for the enantioselective addition of diethylzinc to aldehydes. The stereochemical outcome of the reactions was controlled solely by the absolute configuration of the benzylic carbon bearing amino group, and both enantiomers of 1-substituted propanol were obtained with up to 98% (S) and 96% (R) enantiomeric excesses.

A new pyrrolidine-derived atropisomeric amino alcohol as a highly efficient chiral ligand for the asymmetric addition of diethylzinc to aldehydes

A highly efficient pyrrolidine-derived atropisomeric amino alcohol, (Sa)-1-[2-diphenylhydroxymethyl-6-(trifluoromethyl)phenyl]-2-(1-pyrrolido)methyl-1H-pyrrole, has been synthesized as a chiral ligand for the enantioselective addition of diethylzinc to some prochiral aldehydes to afford (S)-alcohols. The conversion rates were close to quantitative with good to excellent enantiomeric excesses (up to 95% ee).

Vasicine as tridentate ligand for enantioselective addition of diethylzinc to aldehydes

The first report of natural l-vasicine as tridentate chiral ligand for the enantioselective addition of diethylzinc to a variety of aliphatic and aromatic aldehydes is described. The ligand generates R-isomer of the secondary alcohols upto 98% ee. The qui

Asymmetric preparation of new N, N -dialkyl-2-amino-1,1,2-triphenylethanol catalysts and a kinetic resolution in the addition of diethylzinc to flavene-3-carbaldehydes

Enantiopure N,N-dialkyl-(S)-2-amino-1,1,2-triphenylethanols were prepared using a new synthetic methodology and tested for their ability to catalyze the enantioselective addition of diethylzinc to aldehydes. The structural modification of N-substituents of the catalysts led us to identify N-methyl-N-(S)-1-phenyl-ethyl-substituted 4d as an effective catalyst for the addition. Also disclosed is a kinetic resolution of racemic flavene-3- carbaldehydes with the chiral catalyst.