However, when both carbonyls are similar in pKa they may both function as either the nucleophile or the electrophile, meaning the reaction may form either cross-products or self-products.

[6][7] These vinyloxyboranes proved straightforward to synthesize directly from the desired ketones using DBBT, which has a more electron-withdrawing triflate group in place of the sulfur.

As an extension of his earlier research with trivalent phosphorus as an oxygen acceptor, Mukaiyama began to examine the role of metallic catalysts for the dehydrative Friedel-Crafts alkylation and in particular titanium(IV) tetrachloride.

In 1973, he reported that titanium(IV) chloride treated with zinc powder catalyzed a pinacol coupling of carbonyls in THF which formed an alkene after reflux with 1,4-dioxane.

[10] Published in 1973 as Mukaiyama was in the process of migrating to the University of Tokyo, it is a cross-aldol reaction between a silyl enol ether (typically derived from a carbonyl of choice using the method of Stork[11]) and an aldehyde of choice in the presence of a Lewis acid like titanium(IV) chloride.

The reaction is a landmark case on how activating aldehydes can allow even electronically neutral and weakly nucleophilic compounds like silyl enol ethers to be used as reagents.

Tin(II) goes a step further by having multiple empty orbitals, allowing it to coordinate chiral ligands and induce enantioselectivity.

This reaction is typically performed at very low temperatures (< -50 °C) to stabilize its activated DMSO intermediate and constantly evolves the strong-smelling DMS, making it very difficult to work with at large scales.

The difficulties encountered during their total synthesis prompted Mukaiyama to pursue an alternative method, and in 2001 a room-temperature oxidation involving N-chlorosuccinimide and a catalytic amount of N-t-butylbenzenesulfenamide was developed.

"[21] The combination of the high quality of his work and the over 600 papers that he published in Chemistry Letters played an important role in its spread to other nations.