Rhodium‐Catalyzed Asymmetric Hydroformylation of 1,1‐Disubstituted Allylphthalimides: A Catalytic Route to β³‐Amino Acids

Abstract

The high enantioselective rhodium-catalyzed hydroformylation of 1,1-disubstituted allylphthalimides has been developed. By employing chiral ligand, a series of b 3 -aminoaldehydes can be prepared with up to 95% enantioselectivity. This asymmetric procedure provides an efficient alternative route to prepare chiral b 3 -amino acids and alcohols.

Design and Application of Hybrid Phosphorus Ligands for Enantioselective Rh-Catalyzed Anti-Markovnikov Hydroformylation of Unfunctionalized 1,1-Disubstituted Alkenes

“…Although good regio- and enantioselectivities have been achieved for AHF of monosubstituted and 1,2-disubstituted olefins, in which α-chiral branched aldehydes are formed, AHF of 1,1-disubstituted olefins to provide β-chiral linear aldehydes (as indicated by Keulemans’ empirical rule ) has been much less investigated due to the formidable challenge in terms of enantioselectivity and reactivity. Recently, Buchwald group and Zhang group have reported the Rh-catalyzed asymmetric hydroformylation of an α-alkyl acrylate and 1,1-disubstituted allylphthalimides, respectively. However, unlike the AHF of functionalized 1,1-disubstituted olefins, achieving a highly enantioselective AHF of unfunctionalized 1,1-disubstituted olefins becomes more challenging .…”

Chiral Ligands for Rhodium‐Catalyzed Asymmetric Hydroformylation: A Personal Account

“…Based on the previously developed chiral ligands, some other chiral ligands such as the rigid chiral ligands 9 23 and 10 24 were also reported by Ding and Xia et al for AHF with moderate to good selectivities. Moreover, ligands that have been previously utilized in highly enantioselective hydrogenation, such as ( R , R , R , R )‐Ph‐bpe 11 25,26 and ( R , R )‐BenzP* 12 ,27–29 were also used in AHF and good enantioselectivities were observed.…”

Stereospecific Hydroformylation of 1-Substituted Cyclopent-3-en-1-ols: A Concise Access to Bridged [2, 2, 1] Bicyclic Lactones With A Quaternary Stereocenter

“…16 Therefore, the development of a concise and efficient method to produce bridged [2,2,1] bicyclic lactones is highly desirable. Asymmetric hydroformylation (AHF) represents an efficient approach for asymmetric formation of C-C bond in an atomic economic manner, 17,18,19,20,21,22,23,24,25 and the aldehyde products can be easily converted to versatile functional compounds, such as chiral alcohols, acids, amines and esters, 26,27,28,29,30,31,32,33,34 thus asymmetric hydroformylation has been widely investigated and some significant progress have been made. 35,36,37,38,39,40,41,42,43,44,45 However, asymmetric hydroformylation is very sensitive to the steric hindrance of substrate, which make it difficult to tolerate tri-or tetrasubstituted alkenes.…”