Natural lipases typically recognize enantiomers of alcohols based on the size differences of substituents near the carbinol moiety and selectively react with the R enantiomers of secondary alcohols. Therefore, lipase-catalyzed dynamic kinetic resolution (DKR) of racemic secondary alcohols produces only R enantiomers. We report herein a method for obtaining S enantiomers by DKR of secondary 3-(trialkylsilyl)propargyl alcohols by using a well-known Rselective Pseudomonas fluorescens lipase in combination with a racemization catalyst VMPS4, in which the silyl group reverses the size relationship of substituents near the carbinol moiety. We have already reported R-selective DKR of the corresponding propargyl alcohols without substituents on the ethynyl terminal carbon, and the presence of an easily removable silyl group has enabled us to produce both enantiomers of propargyl alcohols in high chemical yields and with high enantiomeric excess. In addition, immobilization of the lipase on Celite was found to be important for achieving a high efficiency of the DKR.

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Direct nucleophilic substitution of alcohols with thiols or carbon nucleophiles was achieved using a mesoporous silica-supported oxovanadium catalyst (VMPS4). Benzyl and allyl alcohols were compatible in this reaction under mild conditions, affording the products in high yields. The VMPS4 catalyst showed excellent chemoselectivity toward alcohols in the presence of acid-labile functional groups, which is in contrast to that observed for the commonly used Lewis acid catalysts, which exhibit poor selectivity. The VMPS4 catalyst could be recycled by simple centrifugation, and the catalytic activity was maintained over seven cycles.

A method for enantiodivergent production of S and R propargylic alcohols from their racemates by using commercial lipase‐based dynamic kinetic resolution achieves quantitative conversion of the racemates into optically pure substances. The right and left hands, wearing jeweled rings indicating individual reaction steps, lead to opposite enantioselection, producing S and R alcohols, respectively. The order of the jewels is key to the enantioswitch. More information can be found in the Research Article by S. Akai and co‐workers (DOI: 10.1002/chem.202202437).

The Cover Feature shows the chemoselective, direct nucleophilic substitution of alcohols. An alcohol and an ester are competing in the Tokyo Olympics steeplechase passing through the Olympic symbol, representing a mesoporous silica‐immobilized oxovanadium catalyst, developed in our group. The alcohol is now on the verge of winning the race, i.e. the direct nucleophilic substitution with a sulfur or carbon nucleophile, accompanied by generation of a molecule of water as the only by‐product. More information can be found in the Full Paper by S. Akai et al.