X-ray crystal structure of 3 b with thermal ellipsoids drawn at the 50% probability level; most hydrogen atoms are omitted for clarity. Selected bond lengths [Å] and angles [°]: Zr1–N1 1.909(4), Zr1–C1 2.358(5), C1–Li1 2.17(1), N1–Li1 2.01(1), Zr1–C100 2.3763(5), Zr1–C101 2.3589(5), Li1–O1 1.88(1), N1–C2 1.473(6); Zr1-N1-Li1 91.1(3), Zr1-C1-Li1 76.1(3), C1-Li1-N1 98.1(5), Zr1-N1-C2 167.0(3), C101-Zr1-C100 127.95(2).