ORGANIC SYNTHESES VIA TRANSITION-METAL COMPLEXES .75. PHOSPHINONAPHTHALENES AND PHOSPHINOINDENES BY CYCLIZATION OF ALKYNYL CARBENE COMPLEXES (M=CR, W)

1-Amino-2-ethoxy-4-phosphinonaphthalenes 6a,b (>90% yields) are obtained from (phenylalkynyl)carbene complexes (CO)(5)M=C(OEt)-C drop C-Ph (M = Cr, W) 1 by a novel two-step carbene/alkyne benzannulation, The first step involves the formation of(E)-(2-phenyl-2-phosphinoethenyl)carbene complexes (CO)5M=C(OEt)-CH=C(Ph)-PR(2) (E)-3a-c by 3-addition of secondary phosphines HPR(2) (R = t-Bu, c-C6W11) 2a,b to 1. A subsequent addition of isocyanides R(1)NC (R = t-Bu, c-C6H11) 4a,b to (E)-3a-c yields ketene imine complexes (Co)(5)M[R(1)N=C=C(OEt)-CH=C(Ph)-PR(2)] A by the ins ertion of 4 into the M=C bond of 3. (Metal-free) ketene imines are generated from A by ligand displacement with 4 and cyclize spontaneously to 6. Thermolysis of(E)3a-c affords (CO)(5)M phosphinoindene complexes 9 and 10. Reaction of 9 or 10 with pyridine yields phosphinoindenes 12 and pyridine complexes (CO)(5)M(C5H5N) 11. 10a, C24H29CrO6P, was characterized by X-ray diffraction. It crystallizes in space group P ($) over bar 1 No. 2 with cell parameters a = 9.412(1) Angstrom, b = 11.455(2) Angstrom, c 11.962(2) Angstrom, = 89.10(1)degrees, beta = 79.09(1)degrees, gamma = 88.60(1)degrees, Z = 2, R(1) = 0.063, and wR(2) = 0.117.