Bochet Research Group has recently published a new article in the journal Photochemical & Photobiological Sciences, entitled "3,3',5,5'-Tetramethoxybenzoin: a forgotten photolabile protecting group". 

https://link.springer.com/article/10.1007/s43630-021-00150-7#Sch2

ABSTRACT

Although reported several decades ago, 3,3',5,5'-tetramethoxybenzoin esters have not been used as a common photolabile protecting group, contrary to their unsymmetrical 3?,5?-dimethoxybenzoin analogues. While the properties of the latter are superior, their tedious synthesis and chemical instability represent a drawback. In this article, we describe a reliable synthetic access to the symmetrical tetramethoxybenzoin derivatives, and show that their photochemical behaviour remain interesting, in particular chromatically orthogonality with respect to nitroveratryl esters.