Fig. 4
From: Multiyne chains chelating osmium via three metal-carbon σ bonds
Synthesis of CCCC-type chelates from allene group substituted diynes. a Allene group substituted diynes as ligand precursors to access CCCC-type chelates. b X-ray structure of the cation of 6 drawn with 50% probability (phenyl groups in PPh3 are omitted for clarity). Selected bond distances (Å) and bond angles (deg): Os–C1 2.017(7), Os–C4 2.074(7), Os–C7 2.015(8), Os–C8 2.270(7), C1–C2 1.383(11), C2–C3 1.403(11), C3–C4 1.381(10), C4–C5 1.395(11), C5–C6 1.385(10), C6–C7 1.349(12), C7–C8 1.403(11), Os–C1–C2 119.1(6), C1–C2–C3 114.4(7), C2–C3–C4 112.8(7), C3–C4–Os 118.0(6), C1–Os–C4 75.7(3), Os–C4–C5 117.9(5), C4–C5–C6 113.8(7), C5–C6–C7 111.4(7), C6–C7–Os 123.4(6), C7–Os–C4 73.4(3), Os–C7–C8 81.1(5), C7–C8–Os 61.3(4), C8–Os–C7 37.6(3)
