, H NMR is given in the supplementary information. ? Synthesis: Complexes 1 and 2 were prepared in (60-90%) yield by reacting LaI3(thf)4 with tpztn or tpzen in anhydrous acetonitrile

H. Nmr, , vol.3, p.400

, MHz, 298 K), ? (ppm): for 1:8.73 ( H3, d, 4H), 8.98 (H6, dd, 4H), vol.8

, § Crystal data: for complex 1a, [La(tpztn)I2]I, C23H26I3N10La: M= 962.15, monoclinic, P2(1)/n, a = 17, vol.635

Å. , ?. , and V. , ) Å, V = 14630.3(11) Å 3 , Z = 18, Dc = 2.266 g cm -3 , µ = 7.876 mm -1 . 7890 independent reflections (2?max = 57.8) were collected at 223(2) K. R1[F> 4?(F)] = 0.0306, wR2 = 0.0705. Maximum/minimum residual electron density: 2.737 and -1.570 e.Å -3 . Crystal data for complex 2, vol.110, 2944.

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