A MIL-101–SO₃H MOF was synthesized using commercially available materials. The as-synthesized MIL-101–SO₃H was characterized by SEM, XRD, FTIR, BET and TGA. An efficient and diastereoselective homo-dimerization of 2H-chromenes catalysis was achieved using the sulfonyl derived MIL-101 MOF as a catalyst. A benzopyranobenzopyran polycyclic structure was generated in high yield and diastereoselectivity under mild catalytic reaction conditions. Furthermore, a regio-isomer was observed when 2H-chromene bears different substitution groups, furnishing chromeno[2,3-b]chromene dimer in high yield and good diastereoselectivity. A mechanism is proposed with a tandem rearrangement/hetero-Diels–Alder reaction sequence which is supported by evidence. In addition, the acid MIL-101 MOF catalyst can be recycled ten times without compromising the yield and selectivity.

中文翻译：

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通过磺酰基衍生的MIL-101 MOF催化的邻甲醌甲基化物中间体进行的 2 H-苯甲基二聚体轻松实现†

MIL-101–SO ₃ H MOF是使用市售材料合成的。合成后的MIL-101-SO ₃ H的特征在于SEM，XRD，FTIR，BET和TGA。使用磺酰基衍生的MIL-101 MOF作为催化剂，可实现2 H-苯甲基二烯催化的高效非对映选择性均二聚。在温和的催化反应条件下，以高收率和非对映选择性生成了苯并吡喃并苯并吡喃多环结构。此外，当2 H-色烯带有不同的取代基时，观察到一个区域异构体，从而提供了chromeno [2,3- b] chromene二聚体，收率高，非对映选择性好。提出了一种具有串联重排/杂-Diels-Alder反应序列的机制，这得到了证据的支持。此外，酸性MIL-101 MOF催化剂可以循环使用十次，而不会影响收率和选择性。