217312-38-4

Upstream product

• 930-68-7 cyclohexenone 
• 201852-49-5 potassium (E)-trifluoro(styryl)borate 
• 6783-05-7 trans-2-phenylvinylboronic acid 
• 536-74-3 phenylacetylene 
• 93296-15-2 C₈H₇AlCl₂ 
• 1365919-22-7 (E)-dimethyl(styryl)aluminum 
• 6783-04-6 (E)-2-(2'-phenylethenyl)-1,3,2-benzodioxaborole 

Relevant academic research and scientific papers

4,8-disubstituted bicyclo[3.3.1]nona-2,6-dienes as chiral ligands for rh-catalyzed asymmetric 1,4-addition reactions

C2-symmetric chiral diene ligands based on 4,8-endo,endo-disubstituted bicyclo[3.3.1]nona-2,6-diene framework have been designed and synthesized. The rhodium complexes of the dienes, which were obtained in a few straightforward steps from enantiomerically pure bicyclo[3.3.1]nonane-2,6-dione, exhibited excellent catalytic activity and high enantioselectivity (up to 96% ee) in the conjugate addition reaction of arylboronic acids to cyclic enones under mild reaction conditions with high atom efficiency. Chiral C2-symmetric 4,8-endo,endo-disubstituted bicyclo[3.3.1]nona-2,6-diene ligands were synthesized from easily available bicyclo[3.3.1]nonane-2,6-dione and utilized in the asymmetric 1,4-addition reaction of arylboronic acids to cyclic enones. The catalyst prepared in situ from ligand 4b and [RhCl(C2H4)2]2 exhibited excellent catalytic activity and high enantioselectivity (up to 96% ee) under mild reaction conditions with high atom efficiency.

Enantioselective 1,4-additions of ClMeAl(CHCHR) (R = alkyl, alkenyl, Ph) to cyclohexenones

Chloromethylvinyl alanes (E)-ClMeAl(CH=CHR) prepared directly from terminal alkynes undergo 1,4-addition to cyclohexenone and 3-methylcyclohexenone in moderate to good yield (30-70%) and good to excellent stereoselectivity (80-98% ee) using readily availa

Formation of quaternary stereogenic centers by copper-catalyzed asymmetric conjugate addition reactions of alkenylaluminums to trisubstituted enones

Alkenylaluminums undergo asymmetric copper-catalyzed conjugate addition (ACA) to β-substituted enones allowing the formation of stereogenic all-carbon quaternary centers. Phosphinamine-copper complexes proved to be particularly active and selective compared with phosphoramidite ligands. After extensive optimization, high enantioselectivities (up to 96 % ee) were obtained for the addition of alkenylalanes to β-substituted enones. Two strategies for the generation of the requisite alkenylaluminums were explored allowing for the introduction of aryl- and alkyl-substituted alkenyl nucleophiles. Moreover, alkyl-substituted phosphinamine (SimplePhos) ligands were identified for the first time as highly efficient ligands for the Cu-catalyzed ACA. Chiral synthesis made easy: The copper-catalyzed conjugate addition of alkenylaluminum reagents to 3-substituted cyclic enones allows for the formation of all-carbon chiral quaternary centers (see scheme; CuTC=copper(I) thiophene-2-carboxylate). Chiral phosphinamine (SimplePhos) ligands were found to be highly efficient for this transformation.

Application of chiral tetrahydropentalene ligands in rhodium-catalyzed 1,4-addition of (E)-2-phenylethenyl- and (Z)-propenylboronic acids to enones

Chiral tetrahydropentalenes (3aR,6aR)-1 have been prepared and used as ligands in the Rh-catalyzed 1,4-addition of 1-alkenylboronic acids to cyclic enones 5. It has been discovered that the stereochemistry of the reaction was controlled by the steric properties of the aryl groups in 1 rather than their electronic nature. In the vinylation with (E)-2-phenylethenylboronic acid 5, ligands (3aR,6aR)-1 provided enantioselectivity up to 87% ee and gave high yields of ethenylketones 6 in the presence of 1 (6.6 mol %). The configuration of all ketone products obtained with (3aR,6aR)-1 is (S). Rh-catalyzed reaction of cyclopentenone 4a and (Z)-propenylboronic acid 7 in the presence of ligands (3aR,6aR)-1 yielded at 50 °C an inseparable mixture of (Z)- and (E)-ketones 8 with (Z)-8 as the major product and both in only moderate enantiomeric excess.

Chiral dihydrobenzofuran-based diphosphine (BICMAP): Optical resolution and application to rhodium(I)-catalyzed asymmetric 1,4-addition of aryl- and alkenylboronic acids to cyclic enones

Chiral dihydrobenzofuran-based diphosphine ligand (BICMAP) 1 was used as a ligand for the rhodium(I)-catalyzed asymmetric 1,4-addition of arylboronic acids to cyclic enones up to 99% ee. We also found that the BICMAP-rhodium system was an efficient catalyst for the 1,4-addition of alkenylboronic acids to 2-cyclohexenone in good enantioselectivities.

Highly enantioselective alkenylation of cyclic α,β-unsaturated carbonyl compounds as catalyzed by a rhodium-diene complex: Application to the synthesis of (S)-pregabalin and (-)-α-kainic acid

Rhod to addition: An efficient asymmetric conjugate-addition reaction of alkenyltrifluoroborates and α,β-unsaturated carbonyl compounds, as catalyzed by a rhodium-diene complex, was developed. The products were obtained in high yield and high levels of enantioselectivity. The methodology was applied to a concise synthesis of (S)-pregabalin and (-)-α-kainic acid (see scheme).

Highly enantioselective alkenylation of cyclic α,β-unsaturated carbonyl compounds as catalyzed by a rhodium-diene complex: Application to the synthesis of (S)-pregabalin and (-)-α-kainic acid

Rhod to addition: An efficient asymmetric conjugate-addition reaction of alkenyltrifluoroborates and α,β-unsaturated carbonyl compounds, as catalyzed by a rhodium-diene complex, was developed. The products were obtained in high yield and high levels of enantioselectivity. The methodology was applied to a concise synthesis of (S)-pregabalin and (-)-α-kainic acid (see scheme).

Readily accessible chiral diene ligands for Rh-catalyzed enantioselective conjugate additions of boronic acids

Enabled by the broad scope of the Pd-catalyzed asymmetric alkylation of meso- and d,l-divinylethylene carbonate, several chiral diene ligands were prepared in two steps from commercial materials. Subsequently, these ligands were evaluated in the Rh-catalyzed asymmetric conjugate addition of boronic acids to enones.

Chiral sulfoxide-olefin ligands: Completely switchable stereoselectivity in rhodium-catalyzed asymmetric conjugate additions

Have it both ways: A novel class of chiral sulfoxide-olefin ligands was synthesized from a single chiral source. These ligands were evaluated in rhodium-catalyzed 1,4-additions of arylboronic acids to electron-deficient olefins, and remarkable olefin-directed reversal of stereoselectivity (up to >99 ee, R isomer; 98 ee, S isomer) was observed when the reversal ligand pair L1 (branched olefin) and L2 (linear olefin) were utilized (see scheme). Copyright

Sulfoxide-alkene hybrids: A new class of chiral ligands for the Hayashi-Miyaura reaction

Sulfoxide-alkene hybrids are introduced as a new class of chiral heterodentate ligands for the Hayashi-Miyaura reaction. The synthesis of these ligands was achieved without the use of protecting groups. A chiral resolution was performed via simple column-chromatographic separation of the diastereomeric ligands. Both diastereomers proved to be excellent ligands in Rh-catalyzed 1,4-addition reactions, furnishing chiral products with high enantioselectivities and, remarkably, opposite stereoconfigurations.