SYNTHESIS, STRUCTURE, AND REACTIVITIES OF TRIFLUOROMETHYL-SUBSTITUTED(PI-VINYLCARBENE)IRON COMPLEXES

Bis(triphenylphosphine)nitrogen(1+) tetracarbonylhydridoferrate reacts with hexafluoro-2-butyne to give ,3-bis(trifluoromethyl)acryloyl]tric arbonylferrate (1) in 90% yield. Complex 1 crystallizes in the triclin ic space group P $$($) over bar 1 with a = 13.029(6) Angstrom, b = 16. 812(9) Angstrom, c = 10.341(8) Angstrom, alpha = 103.61(5)degrees, bet a = 96.64(5)degrees, gamma = 68.29(4)degrees, and Z = 2. Complex 1 rea cts with (CH3)(3)OBF4 to give rifluoromethyl)prop-2-en-1-ylidene]trica rbonyliron (4). Complex 4 reacts with pyrrolidine to give rifluorometh yl)prop-2-en-1-ylidene]tricarbonyliron (6), which belongs to the monoc linic space group P2(1) with a = 8.058(2) Angstrom, b = 10.847(4) Angs trom, c = 17.766(4) Angstrom, beta = 99.00(2)degrees, and Z = 4. Compl ex 4 reacts with triphenylphosphine to afford hyl)vinylketene]dicarbon yl(triphenylphosphine)iron (8). Complex 4 reacts with 2 mol equiv of c arbon monoxide to give -4,5-bis(trifluoromethyl)ferracyclopent-3-en-2- one (9). Complex 4 reacts with ethoxyethyne to give [2 + 3] adducts if luoromethyl)-1,3-cyclopentadiene]triacarbnyliron (13). Complex 13 crys tallizes in the triclinic space group P $$($) over bar 1 with a = 7.61 77(8) Angstrom, b = 14,646(2) Angstrom, c = 7.488(1) Angstrom, alpha = 99.73(1)degrees, beta = 98.08(1)degrees, gamma = 98.97(1)degrees, and Z = 2.