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The development of new, more efficient Friedel-Crafts benzylation methodologies that provide access to 1,1-diarylalkanes is an important objective of interest for the production of pharmaceuticals and fine chemical products. In this regard, this study introduces a novel synthetic route to 1,1-diarylalkanes conducted in the Deep Eutectic Solvent (DES) 3 FeCl 3  ⋅ 6 H 2 O/Gly, which serves as both a reaction medium and promoter. Under these conditions, Friedel-Crafts benzylations of various arenes bearing activating and deactivating ortho-/para-directing groups, can be performed using diverse benzylating reagents such as styrenes, alcohols, acetates, ethers, and chlorides. Importantly, highly electronically deactivated electrophiles, including those with CF 3 and NO 2 groups, are suitable substrates. This methodology provides a wide range of asymmetric 1,1-diarylalkanes (up to 132 examples) with generally good yields and high regioselectivities. The efficiency of this approach was demonstrated with the multigram-scale synthesis (10 mmol) of 1-phenyl-1-xylyl ethane (PXE), a liquid with great industrial applicability. Moreover, the Fe(III)-based DES could be reused for 20 consecutive cycles with no appreciable erosion of the yields., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)