Catalysts Produce Complex Spirocyclic Molecules in One Step Catalysts for the first asymmetric [3+2] allylsilane annulation make new silyl spirocycles: R1
R3Si
[3+2] allylsilane annulation SiR3
O
Catalysts are the matchmakers of the laboratory, connecting simple molecules together to produce more complex molecules that are important for medicines, materials & energy. From metal catalysts to phosphoric acids, these chiral catalysts help us discover new molecules and use more environmentally-friendly processes.
HO
R1
O
with TMSCl promoter
Catalysts for an enantioselective Pictet-Spengler spirocyclization:
N R
ScCl2(SbF6)-pybox catalyst
R
O
N O H
R1
N R
X = OH
NH O
H3CO
catalyst (20 mol %)
N H
NR X-ray structure
Na2SO4 R1
O N R
X-ray structure
O X = SiR3
95-99% ee
NH2
H3CO +
R1
O
O N
Oxidative Cleavage of C-Si
Ar
up to 99% yield up to 96% ee O
O P O OH Ar
Ar = (R)-9-anthracenyl Ar = (S)-2,4,6-tri-i-Pr-phenyl
Spiroindolones exhibit anti-malaria activity same product configuration
