Chiral BINOL-centered dendrimers for the enantioselective Lewis acid catalyzed diethylzinc addition to aldehydes

Li, Guohua; Fan, Qing‐Hua; Yang, X.-M.; Chen, Xiaomin

doi:10.3998/ark.5550190.0004.214

Cited by 9 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…BINOL 3,3′-dicarboxylic acid and its derivatives were prepared from the ortho-lithiation of BINOL-MOM. As shown in Scheme , after ortho-lithiation with n BuLi in THF, CO 2 was added as the electrophile, which after treatment with HCl in an alcoholic solution gave ( R )- 267 in 70% yield. , The dicarboxylic acid BINOL has been used as the precursor to prepare other BINOL derivatives for various applications. − For example, ( R )- 267 was converted to several amide derivatives ( R )- 268 with >99% ee. These chiral amides were used to catalyze the Simmons–Smith cyclopropanation of allylic alcohols with ZnEt 2 and CH 2 I 2 to give chiral cyclopropanes, and the asymmetric reaction of ZnEt 2 with propargyl aldehyde. , …”

Section: Ortho-lithiation At 3-positionmentioning

confidence: 99%

Regioselective Substitution of BINOL

2024

Chem. Rev.

View full text Add to dashboard Cite

1,1′-Bi-2-naphthol (BINOL) has been extensively used as the chirality source in the fields of molecular recognition, asymmetric synthesis, and materials science. The direct electrophilic substitution at the aromatic rings of the optically active BINOL has been developed as one of the most convenient strategies to structurally modify BINOL for diverse applications. High regioselectivity has been achieved for the reaction of BINOL with electrophiles. Depending upon the reaction conditions and substitution patterns, various functional groups can be introduced to the specific positions, such as the 6-, 5-, 4-, and 3-positions, of BINOL. Ortho-lithiation at the 3-position directed by the functional groups at the 2-position of BINOL have been extensively used to prepare the 3- and 3,3′-substituted BINOLs. The use of transition metal-catalyzed C–H activation has also been explored to functionalize BINOL at the 3-, 4-, 5-, 6-, and 7-positions. These regioselective substitutions of BINOL have allowed the construction of tremendous amount of BINOL derivatives with fascinating structures and properties as reviewed in this article. Examples for the applications of the optically active BINOLs with varying substitutions in asymmetric catalysis, molecular recognition, chiral sensing and materials are also provided.

show abstract

Section: Ortho-lithiation At 3-positionmentioning

confidence: 99%

Regioselective Substitution of BINOL

2024

Chem. Rev.

View full text Add to dashboard Cite

show abstract

“…When incorporated in polymers or resins, even a single BINOL residue can have important effects on the optical rotation of the material, as was shown for a dendrimer with a BINOL core. [ 37 ]…”

Section: Introductionmentioning

confidence: 99%

High Refractive Index, Enantiopure Silicones Based on BINOL

Meléndez-Zamudio

Silverthorne

Brook

2022

Macromol. Rapid Commun.

View full text Add to dashboard Cite

The high refractive index aromatic compound, binaphthol (BINOL), is readily incorporated into silicone polymer chains using the Piers–Rubinsztajn (PR) reaction; alternating and random linear copolymers, and elastomers are available. The highest refractive index (RI) materials are BINOL rich. It is not possible to directly make high refractive index linear polymers with very short HSi‐capped, telechelic silicone chains, as they do not react cleanly. However, chain extending short vinyl‐capped BINOL macromers with simple arylsilanes using hydrosilylation leads to polymers with a molar mass of up to 8000 and refractive indices of up to 1.58. Elastomers are prepared using similar processes. The reactions are facile to practice and suggest BINOL can be harnessed in these and other processes to augment RI.

show abstract

“…6 The resulting protected (S)-3 was then lithiated with n-BuLi followed by carboxylation with CO 2 to give (S)-4. 7 The obtained diacid 4 was further esterified with CH 3 I to give the key intermediate diester (S)-5. Finally, the resulting diester was refluxed with the aryl Grignard reagents (10 equiv) in THF to afford the bifunctional BINOL ligands (1a-1e) in moderate to high yields.…”

mentioning

confidence: 99%