Lithiated Carbamates: Chiral Carbenoids for Iterative Homologation of Boranes and Boronic Esters

Enantiospecific sp2–sp3 coupling of secondary and tertiary boronic esters

“…We began our studies with the addition of 2-lithiofuran to boronic ester (R)-1a, (prepared by our lithiation-borylation methodology) 39 and explored a range of electrophiles (see SI). Of the electrophiles tested, NBS was found to be optimum, reacting rapidly at low temperature, and furnishing the product with complete stereospecificity (100% es) (Figure 1c).…”

“…A range of enantioenriched secondary 39 and tertiary boronic esters [40][41][42] were then prepared by lithiation-borylation methodology or by hydroboration ( Figure 2, see SI for details) and subsequently tested under these optimized reaction conditions (Table 1). Figure 2.…”

Awards of the GDCh at the Wissenschaftsforum

“…In a Communication currently published online in Angewandte Chemie he reports the use of lithium carbamates as chiral carbenoids for the iterative homologation of boranes and boronic acids. [7] Aggarwal received his PhD in 1986 under the supervision of S. Warren (University of Cambridge) and undertook postdoctoral research with G. Stork (Columbia University, New York). In 1988 he became a lecturer at the University of Bath; in 1991 he moved to the University of Sheffield, where he became a professor in 1997.…”

Highly Enantioselective Synthesis of Tertiary Boronic Esters and their Stereospecific Conversion to other Functional Groups and Quaternary Stereocentres

“…[12] We therefore consid-Abstract: Organoboron compounds are useful in asymmetric synthesis. from the reactions of boronic esters with Hoppes lithiated carbamates derived from primary alcohols (Scheme 4).…”