While the rubber compound is certainly much more complex than their proposed mechanism, shown in scheme 2, the attack on the ether linkage of the dibenzyl ether by zinc chloride, as shown, is a viable option for understanding the degradation mechanism in polyether elastomers.
Bell, "Cleavage of dibenzyl ether in the presence of zinc halides," Journal of Catalysis--87, pp.
To a solution of dibenzyl ether 6 (1.13 mg, 2.58 mmol) in anhydrous C[H.sub.2][Cl.sub.2] (20 mL) [BBr.sub.3] (500 [micro]L, 5.28 mmol, 1.025 eq) was added dropwise at -78[degrees]C under argon atmosphere.
Efficient synthesis of (2R,3R)- and (2S,3S)-2,3-diaminobutane-1,4-diol and their dibenzyl ethers. Tetrahedron: Asymmetry, 1997, 8, 1243-1251.