New strategy to the synthesis of (N → B) phenyl[N-alkyliminodiacetate-O,O′,N]boranes: The crystal structure of (N → B) phenyl[N-benzyliminodiacetate-O,O′,N]borane, (N → B)phenyl[N-(4-methyl)benzyliminodiacetate-O,O′,N]borane and (N → B) phenyl[N-phenacyliminodiacetate-O,O′,N]borane

A new, mild and friendly method for the synthesis of (N → B) phenylN-alkyliminodiacetate-O,O′,N]boranes 2–7 is reported. All compounds were identified by ¹H, ¹¹B, ¹³C NMR and their high resolution mass spectra (HRMS) are reported. The structure of the compounds 2, 4 and 5 were established by single crystal X-ray. Compounds 2 and 4 crystallized with two independent molecules 2A, 2B and 4A, 4B, respectively in the asymmetric unit. These molecular structures established the bicyclic structure showing a N → B bond length of 1.666 (2) Å for 2A, 1.675 (2) Å for 2B, 1.675 (3) Å for 4A, 1.663 (3) Å for 4B and 1.679 (2) Å for 5, as well as different torsion angles of the junction, 28.70 (2)° (C11–B1–N6–C17) for 2A, 21.50 (2)° (C11a–B1a–N6a–C17a) for 2B, 25.76 (0.26)° (C11–B1–N6–C17) for 4A, 21.96 (0.28)° (C11a–B1a–N6a–C17a) for 4B and −29.22 (0.20)° (C5–N1–B1–C13) for 5.