10.1021/acs.orglett.6b01970.s001 Zhi-Wei Zhang Zhi-Wei Zhang Hong Xue Hong Xue Hailing Li Hailing Li Huaiping Kang Huaiping Kang Juan Feng Juan Feng Aijun Lin Aijun Lin Shouxin Liu Shouxin Liu Collective Synthesis of 3‑Acylindoles, Indole-3-carboxylic Esters, Indole-3-sulfinic Acids, and 3‑(Methylsulfonyl)indoles from Free (N–H) Indoles via Common <i>N</i>‑Indolyl Triethylborate American Chemical Society 2016 Indole C 3 functionalization acid chlorides indole Collective Synthesis indolyl triethylborate reaction proceeds C 7 positions thionyl chloride methylsulfonyl chloride 2016-07-25 23:49:23 Journal contribution https://acs.figshare.com/articles/journal_contribution/Collective_Synthesis_of_3_Acylindoles_Indole-3-carboxylic_Esters_Indole-3-sulfinic_Acids_and_3_Methylsulfonyl_indoles_from_Free_N_H_Indoles_via_Common_i_N_i_Indolyl_Triethylborate/3498566 A general and direct C3 functionalization of free (N–H) indoles with readily available electrophiles such as acid chlorides, chloroformates, thionyl chloride, and methylsulfonyl chloride via a common <i>N</i>-indolyl triethylborate intermediate is reported. The reaction proceeds smoothly under mild conditions in up to 93% yield. Indoles with substituents at the C2, C4, C5, C6, and C7 positions are well tolerated. The easy accessibility of a variety of important 3-acylindoles, indole-3-carboxylic esters, indole-3-sulfinic acids, and 3-(methylsulfonyl)­indoles demonstrates the high degree of compatibility and practicability of this method.