The article written by Dr. Qian Pengcheng from the College of Chemistry & Materials Engineering as the first corresponding author entitled “Gold-catalysed asymmetric net addition of unactivated propargylic C–H bonds to tethered aldehydes” was published in Nature·Catalysis (DOI: 10.1038/s41929-020-00569-8).

This article studies the asymmetry of aldehydes. The asymmetric propargyl alcoholization of aldehydes can generate various chiral allyl alcohol, which is a very important reaction process in the field of organic chemistry. In such asymmetric synthesis processes, it is necessary to bond to Si, B, Al, Cu, Sn, Cr, In and other metal/non-metal propargyl structures as propargyl nucleophiles, thus participating in the propargylation reaction process in-situ or directly as raw materials.

Compared with other traditional methods, the direct addition of the propargyl C-H bond to the carbonyl group is an atomic economy method, which can avoid the consumption of stoichiometric metal or substrate, and avoid the generation of stoichiometric metal salt waste. At the same time, the reaction can proceed through a continuous deprotonation-propargylation-protonation catalytic reaction. However, this catalytic reaction has not been reported in the current literature. At present, only achiral selectivity can be achieved, and it cannot be compatible with molecules containing α-C(sp3)-H bonds in aldehyde substrates. Conceptually, this substrate cannot be achieved by normal basic catalysis, because the proton acidity of the propargyl site (pKa>30) is lower than the acidity of the aldehyde group α-H (pKa≈17). Hence, the reaction is easier to proceed through self-aldol condensation reaction.

In view of this, Zhang Liming of UCSB, Qian Pengcheng of Wenzhou University, etc. reported a method to synthesize chiral propargyl alcohol under mild conditions by intramolecular transformation. This reaction synthesizes a chiral bifunctional phosphorus ligand. Through the tertiary organic amine (pKa≈10) on the phosphine ligand, when the acid aldehyde α-H is also present in the substrate molecule, the propargyl C-H bond of the molecule is effectively activated

The reaction has a wide range of substrate and functional group compatibility, and can synthesize homopropargyl alcohol with cyclopentane/cyclohexane with excellent enantioselectivity and trans selectivity. Whether the substrate contains chiral sites or not, both showed good reactivity. As a green and efficient synthesis method, the development of this reaction has important academic significance and application value.

Nature·Catalysis is a top international journal in the field of catalysis, with the IF of 30.5 in 2020 and an immediate IF of 42.

It is also the first time when the academic staff of Wenzhou University published an article in this journal.