A simple synthetic approach to homochiral 6- and 6′-substituted 1,1′-binaphthyl derivatives
作者:Heiko Hocke、Yasuhiro Uozumi
DOI:10.1016/s0040-4020(02)01584-3
日期:2003.1
Various homochiral binaphthyl derivatives having functional groups at the 6-position are important key intermediates for the immobilization of binaphthyl compounds on various solid-supports and have been prepared from commercially available 1,1'-bi-2-naphthol via controlled monopivalation of the 2-hydroxyl group and electrophilic aromatic substitution at the 6-position. (S)-2,2'-Bis-((S)-4-alkyloxazol-2-yl)-6-(2-methoxycarbonyl)ethyl-1,1'-binaphthyls (6-functionalized (S,S)-boxax)) were prepared and immobilized on various polymer supports including PS-PEG, PS, PEGA and MeO-PEG resin. (C) 2003 Elsevier Science Ltd. All rights reserved.
The artificial binaphthyl amino acid 6-amino-6′-carboxyethyl-2-methoxy-2′-hydroxy-1,1′-binaphthyl (Bna): synthesis and assembly of Bna peptides
作者:Melanie Thoß、Rüdiger W. Seidel、Martin Feigel
DOI:10.1016/j.tet.2010.08.066
日期:2010.10
The new binaphthyl-based amino acid 6-amino-6'-carboxyethyl-2-methoxy-2'-hydroxy-1,1'-binaphthyl (Bna) is presented, which combines the axially chiral binaphthyl core, a phenolic OH-group as well as terminating amino and carboxyl groups in one structure. The large aromatic rings of the compound provide molecular spacing and pi-surface attraction in assembled Bna oligoamides. The synthesis of Bna derivatives is reported, both with the (R)- and with the (S)-binaphthyl skeleton. Several dipeptides of (R)or (S)-Bna units combined with natural amino acids, were prepared as 'building blocks' for the synthesis of extended Boa peptides. The tetrapeptide Boc-(S)-Val-(S)-Bna(OH)-(S)-Val-(S)-Bna(OPiv)-O-n-But (12) and the pentapeptide Boc-(S)-Val-(S)-Bna(OH)-(S)-Val-(S)-Bna(OH)-Gly-OH (13) were prepared via conventional solution phase synthesis and solid phase synthetic techniques, respectively. Compound 12 shows an interesting dynamic H-1 NMR spectrum suggesting compact and aggregated forms in dichloromethane. Compound 13 accelerates the enolisation of acetone. The use of more complex Bna peptides as organo catalysts is proposed. (C) 2010 Elsevier Ltd. All rights reserved.
Practical and Scalable Kinetic Resolution of BINOLs Mediated by a Chiral Counterion
作者:Benjamin A. Jones、Tudor Balan、John D. Jolliffe、Craig D. Campbell、Martin D. Smith
DOI:10.1002/anie.201814381
日期:2019.3.26
BINOLs are valuable and widely used building blocks, chiral ligands, and catalysts that are effective across a remarkable range of different chemical transformations. Here we demonstrate that an ammonium salt catalyzed kineticresolution of racemic BINOLs with benzyl tosylate proceeds with s up to 46. This is a scalable and practical process that can be applied across >30 different C2‐ and non‐C2‐symmetric