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https://doi.org/10.1021/jo00105a054

has been cited by the following article:

• TITLE: Selective Monoprotection of Symmetrical Diols in a Flow Reactor

  AUTHORS: Hisashi Masui, Masaru Takizawa, Yuki Sakai, Yasuhiro Kajiwara, Kiyofumi Wanibuchi, Mitsuru Shoji, Takashi Takahashi

  KEYWORDS: Desymmetrization, Selective Monoprotection, Flow Synthesis, Diols, Tetrahydropyranylation

  JOURNAL NAME: International Journal of Organic Chemistry, Vol.8 No.2, June 22, 2018

  ABSTRACT: Desymmetrization reactions provide a powerful approach for the construction of complex molecules. Various methods have been developed for the selective monoprotection of symmetrical diols; however, their application to large-scale operations is limited. In this study, the monotetrahydropyranylation of symmetrical diols in a flow reactor has been developed, whereby the length of the flow reactor tube and the amount of acid were optimized. A higher selectivity for the monoprotected derivative was observed when the reaction was performed in a flow reactor compared with that observed in a conventional batch experiment. The efficient flow method developed herein can be applied to large-scale synthesis by numbering up the flow reactor without affecting the selectivity and yield. Since monoprotection can be achieved without using a large excess of diol, our developed flow method is effective when expensive diol must be used.