Making molecules

The major theme of research in the group of prof. Petri Pihko is to establish novel and efficient strategies for chemical synthesis with the help of catalytic transformations, especially organo- and enzyme catalysis, and oxidative catalysis. We are developing ready-to-use catalytic tools for synthesis as well as applying them to construct biologically and structurally interesting natural products and industrially relevant targets. We pay special attention not only to the generality and wide scope of the transformations, but also to understanding the underlying mechanistic and structural details through physical organic chemistry.

Selected publications

Organocatalysts Fold to Generate an Active Site Pocket for the Mannich Reaction

ACS Catal. 2017, 7 (5), 3284–3294

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Catalytic performance of foldamer catalysts in Mannich reactions may not be due to cooperative effects of intramolecular hydrogen bonds but simply due to the presence of the folded structure that provides an active site pocket, accommodating the substrate and at the same time impeding undesirable side reactions.

A Catalyst Designed for the Enantioselective Construction of Methyl- and Alkyl-Substituted Tertiary Stereocenters

Angew. Chem. Int. Ed. 2016, 55, 669–673

Reported herein is a catalytic enantioselective method for accessing these chiral building blocks using the Mukaiyama–Michael reaction between silyl ketene thioacetals and acrolein. The catalytic process allows rapid access to chiral thioesters, amides, aldehydes, and ketones bearing an α-methyl stereocenter with excellent enantioselectivities, and allowed rapid access to the C4–C13 segment of marine natural product (−)-bistramide A.

Cross-Dehydrogenative Couplings between Indoles and β-Keto Esters: Ligand-Assisted Ligand Tautomerization and Dehydrogenation via a Proton-Assisted Electron Transfer to Pd(II)

J. Am. Chem. Soc. 2014, 136 (17), 6453–6462

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Cross-dehydrogenative coupling reactions between β-ketoesters and electron-rich arenes, such as indoles, proceed with high regiochemical fidelity with a range of β-ketoesters and indoles. The experimental results indicate that the reaction proceeds via two catalytic cycles. Cycle A, the dehydrogenation cycle, produces an enone intermediate. The dehydrogenation is assisted by N-methylindole, which acts as a ligand for Pd(II). The coupling is completed in cycle B, where the enone is coupled with indole.