We report on the synthesis and structural features of NMe₂-modified β-diketiminate-supported boron difluoride compounds (LArBF₂: L^Ar = [HC(NAr)₂(CNMe₂)₂]^–; L^Ph: Ar = Ph; L^Tol: Ar = p-tolyl; L^Xyl: Ar = m-xylyl). The title compounds were prepared in moderate yields (~65 %) by in situ deprotonation of the corresponding ligands L^ArH using KH, followed by the addition of BF₃OEt₂. According to solid-state and theoretical analyses of the BF₂ compounds, the lone pair at each NMe₂ group is involved in electron delocalization within the central BC₃N₂ ring. As a result, the N-aryl substituents sterically clash with the NMe₂ groups, causing this central ring to pucker. Several attempts were made to prepare heavy analogues (e.g. L^ArBX2, X = Cl, Br, I) but only unidentifiable product mixtures were observed. It appears that the observed steric clash between the N-aryl substituents and the NMe₂ groups prevented the formation of these heavy analogues.

我们报道了NMe ₂改性的β-二酮基化负载的二氟化硼化合物（LArBF ₂：L ^Ar  = [HC（NAr）₂（CNMe ₂）₂ ] ^–；L ^Ph：Ar = Ph; L ^TOL：Ar为 p -甲苯基;大号^的Xyl：Ar为 米-二甲苯）。通过使用KH对相应的配体L ^Ar H进行原位去质子化，然后添加BF ₃ OEt _2，可以以中等收率（〜65％）制备标题化合物。根据对BF ₂化合物的固态和理论分析，每个NMe ₂基团上的孤对都参与了中心BC ₃ N ₂环内的电子离域。结果，N-芳基取代基在空间上与NMe ₂基团碰撞，导致该中心环起皱。进行了几次尝试以制备重的类似物（例如L ^Ar BX2，X = Cl，Br，I），但仅观察到无法识别的产物混合物。似乎观察到的N-芳基取代基和NMe ₂基团之间的空间冲突阻止了这些重类似物的形成。