Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides

• Shengli Zuo,
• Shuxiang Zheng,
• Jianjun Liu and
• Ang Zuo

Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147

• and preparation of suitable salen compounds, sometimes are described as bis-imine Schiff bases. Imines were originally synthesized by Schiff from the condensation of carbonyls with amines [25]. Thereafter, syntheses of salens were extensively reported using timely technologies [26][27][28][29

Achiral bis-imine in combination with CoCl₂: A remarkable effect on enantioselectivity of lipase-mediated acetylation of racemic secondary alcohol

• K. Arunkumar,
• M. Appi Reddy,
• T. Sravan Kumar,
• B. Vijaya Kumar,
• K. B. Chandrasekhar,
• P. Rajender Kumar and
• Manojit Pal

Beilstein J. Org. Chem. 2010, 6, 1174–1179, doi:10.3762/bjoc.6.134

• Anantapur, Anantapur 515002, Andhra Pradesh, India, Institute of Life Sciences, University of Hyderabad Campus, Gachibowli, Hyderabad 500 046, Andhra Pradesh, India 10.3762/bjoc.6.134 Abstract A bis-imine (prepared via a new FeCl3-based method) in combination with CoCl2 facilitated lipase-mediated

• acetylation of the (R)-isomer of a racemic benzylic secondary alcohol with 91% ees. The methodology was used for the preparation of the known drug rivastigmine. Keywords: acetylation; bis-imine; cobalt chloride; enantioselectivity; lipase; Introduction The development and use of newer synthetic methods for

• preliminary results on the synthesis and identification of a novel ligand for this process (Scheme 1) and its application in the preparation of the known drug rivastigmine [14]. While the uses of bis-imine/transition-metal complexes have been reported for the enantioselective synthesis of chiral compounds [15