The Mukaiyama aldol reaction is one of the various aldol reactions and gives β-hydroxycarbonyl compounds from ketones or aldehydes and
silyl enol ethers or its derivatives in the presence of a
Lewis acid. In this reaction, a single cross-aldol product is produced due to the use of a stable enol silyl ether. The reaction mechanism is considered not to be through a six-membered transition state but through a linear transition state due to the poor ligating property of the siloxy group. Therefore, the stereoselectivity of the product varies depending on the substrates and reaction conditions. The conventional Mukaiyama aldol reaction requires an equivalent amount of Lewis acid, but the new conditions was found to use a catalytic amount of Lewis acid. Furthermore, other conditions using Lewis base and an asymmetric reaction are possible. Many applications have been found, such that it is widely utilized in the synthesis of natural products.