This study aims to perform the chelation of difluoroboron (BF2) to quinacridonequinone (QQ). The resulting dark green solid was determined to be QA‐BF2, which is a BF2 complex of 6,13‐dihydroxyquinacridone (QA‐OH), and not QQ‐BF2, which is a BF2 complex of QQ. This result indicated that QQ‐BF2 was first generated as an O,O‐bidentate chelate, which immediately underwent a two‐electron reduction to produce QA‐BF2. This compound was converted to air‐sensitive QA‐OH by undergoing hydrolysis in argon. Since QA‐OH has a strong electron‐donating property, it easily produced QQ via air oxidation in the solution. QA‐OH also acts as a reducing reagent for quinones. The crystal packing of QA‐OH is a herringbone type with short π⋅⋅⋅π contacts, and a good hole mobility has been suggested by theoretical calculations. Herein, a new synthetic method from QQ to QA‐OH using BF2 chelation and hydrolysis was proposed. QA‐BF2 and QA‐OH are useful organic functional pigments and reducing reagents.

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BF2 chelation to quinacridonequinone (QQ) was performed for the development of new pigments. The resulting dark green solid was determined to be a BF2 complex of 6,13‐dihydroxyquinacridone (QA‐OH). This indicated that a two‐electron reduction occurred in the BF2 chelation, although the electron source was not specified. The BF2 complex underwent hydrolysis in argon to produce QA‐OH as a dark purple solid. Furthermore, QA‐OH was converted to QQ by air oxidation. In this paper, a new synthetic method from QQ to QA‐OH via BF2 complexes is proposed. More information can be found in the Communication by Katsuhiko Ono et al. on page 1452 in Issue 9, 2019 (DOI: 10.1002/asia.201900219).