With Tf2O as the activation reagent, a mild and general method has been developed for the bisphosphonylation of both secondary and tertiary amides. The protocol is highly efficient and chemoselective, and it tolerates a number of sensitive functional groups such as cyano, ester, and aldehyde groups.

Novel chiral imidazo[1,5-a]tetrahydroquinoline N-heterocyclic carbenes derived from β-pinene have been developed. The preliminary studies with both the in situ generated and preformed copper–carbene complexes have shown these chiral NHCs are efficient and selective ligands in the Cu-catalyzed asymmetric conjugate borylation of α,β-unsaturated esters.6,6-Dimethylbicyclo[3.1.1]heptan-2-oneC9H14O[α]D20=+29.8 (c 2.5, CHCl3)Absolute configuration: (1R,5S)Source of chirality: (−)-β-pinene7,7-Dimethyl-5,6,7,8-tetrahydro-6,8-methanoquinolin-2(1H)-oneC12H15NO[α]D20=+71.5 (c 0.9, CH2Cl2)Absolute configuration: (6R,8R)Source of chirality: (−)-β-pinene7,7-Dimethyl-5,6,7,8-tetrahydro-6,8-methanoquinolin-2-yl trifluoromethanesulfonateC13H14F3NO3S[α]D20=-8.9 (c 1.0 , CH2Cl2)Absolute configuration: (6R,8R)Source of chirality: (−)-β-pineneMethyl 7,7-dimethyl-5,6,7,8-tetrahydro-6,8-methanoquinoline-2-carboxylateC14H17NO2[α]D20=-9.8 (c 1.5, CH2Cl2)Absolute configuration: (6R,8R)Source of chirality: (−)-β-pinene7,7-Dimethyl-5,6,7,8-tetrahydro-6,8-methanoquinoline-2-carbaldehydeC13H15NO[α]D20=-27.8 (c 1.0, CH2Cl2)Absolute configuration: (6R,8R)Source of chirality: (−)-β-pinene8,8-Dimethyl-2-phenyl-6,7,8,9-tetrahydro-7,9-methanoimidazo[1,5-a]quinolin-2-ium chlorideC20H21ClN2[α]D20=+60.6 (c 1.1, CH3OH)Absolute configuration: (7R,9R)Source of chirality: (−)-β-pinene2-Mesityl-8,8-dimethyl-6,7,8,9-tetrahydro-7,9-methanoimidazo[1,5-a]quinolin-2-ium chlorideC23H27ClN2[α]D20=+38.4 (c 1.3, CHCl3)Absolute configuration: (7R,9R)Source of chirality: (−)-β-pinene2-(2,6-Diisopropylphenyl)-8,8-dimethyl-6,7,8,9-tetrahydro-7,9-methanoimidazo[1,5-a]quinolin-2-ium chlorideC26H33ClN2[α]D20=+26.0 (c 1.0, CHCl3)Absolute configuration: (7R,9R)Source of chirality: (−)-β-pinene2-(4-Methoxyphenyl)-8,8-dimethyl-6,7,8,9-tetrahydro-7,9-methanoimidazo[1,5-a]quinolin-2-ium chlorideC21H23ClN2O[α]D20=+68.8 (c 0.8, CHCl3)Absolute configuration: (7R,9R)Source of chirality: (−)-β-pinene2-(3,5-Bis(trifluoromethyl)phenyl)-8,8-dimethyl-6,7,8,9-tetrahydro-7,9-methanoimidazo[1,5-a]quinolin-2-ium chlorideC22H19ClF6N2[α]D20=+34.4 (c 1.0, CHCl3)Absolute configuration: (7R,9R)Source of chirality: (−)-β-pinene

This paper summarizes the progress on the total syntheses of natural products accomplished in mainland China during the period from 2006 to 2010. The overview focuses on the first total synthesis of natural products of contemporary interest including alkaloids, cyclopeptides and cyclic depsipeptides, macrolides, terpenoids and steroids, saponins and glycosides. The development of novel synthetic strategies and methodologies, and application of new selective synthetic methods in the total syntheses of natural products are included as well.