Trans Addition of Nucleophiles to q2-Alkyne ... - ACS Publications

The reaction of [CpFeCO[P(OPh),] (q2-MeC=CMe)]+ with Ph2Cu(CN)Li2 yields ... [P(OPh),] [(a-C(Me)=C(Ph)(Me)] is made up of isolated molecules separated...
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Organometallics 1983, 2, 101-105

101

Trans Addition of Nucleophiles to q2-Alkyne Complexes of Iron. Crystal and Molecular Structure of CpFeCO[P(OPh),][ (2)-C(Me)=C(Ph)Me]. Use of Higher Order Organocuprate Reagents Daniel L. Reger,' Kenneth A. Belmore, Edward Mintz, N. G. Charles, E. A. H. Griffith, and E. L. Amma" Department of Chemistry, University of South Carolina, Columbia, South Carolina 29208 Received June 15, 1982

The reaction of [CpFeCO[P(OPh),] (q2-MeC=CMe)]+ with Ph2Cu(CN)Li2yields CpFeCO[P(OPh),![(E)-C(Me)==C(Me)Ph],whereas the reaction of [CpFeCO[P(OPh),](v2-PhC=CMe)]+ with Me2Cu(CN)Li2 yields CpFeCO[P(OPh),][(Z)-C(Me)=C(Ph)Me], the product of the latter reaction being characterized by X-ray crystallography. These alkenyl products will not interconvert under the conditions of the reactions. Thus trans addition of these nucleophiles to $-alkyne complexes is definitively demonstrated for the first time. Furthermore, for the addition reaction to +PhC=CMe the regiochemistry is that which places the incoming nucleophile at the alkyne carbon atom bearing the phenyl substituent. Yields in these reactions are high, demonstrating for the first time the usefulness of higher order organocuprate reagents for addition reactions to unsaturated organic ligands T coordinated to transition metals. The structure of CpFeCO[P(OPh),] [(a-C(Me)=C(Ph)(Me)] is made up of isolated molecules separated by ordinary van der Waals distances. The Fe atom is four-coordinate with CO, P(OPh)3, Cp, and the fourth coordination site made up of an Fe-C 0 bond to the alkenyl group. The P h substituent is clearly at the P-alkenyl carbon atom and cis to the Fe. The alkenyl group is oriented such that the angle between the normals of the Cp lane and the alkenyl plane is 31.1 ( 1 ) O . Crystal data: monoclinic, P2,/c, a = 8.482 (3)& b = 36.84 (1) c = 9.939 (3) A, p = 112.20 (3)'; 2 = 4; P o b d = 1.33 (1)g/cm3, P&d = 1.36 g/cm3; NO = 2545, NV = 361; Rfind = 0.047. The structure was solved by standard heavy-atom methods and refined by full-matrix least squares including anisotropic temperature, anomalous dispersion corrections, and absorption corrections.

Introduction We have recently reported' that a variety of nucleophiles complexes as will add to [CpFeCO(PPh3)(a2-alkyne)]+ shown in eq 1 for the alkyne equal to 2-butyne. This

termination of the stereochemistry of the product, isolated in these cases after column chromatography on alumina, does not definitively define the mode of addition of the nucleophile because metal-alkenyl complexes have been shown to undergo low-energy cis-trans isomerization reactions. T h e best example of this type of isomerization takes place in reaction Z5 T h e initial product of the reaction, Ph

I

PPh3

\c

'Me

/

Me

Me

Nuc = Me, Ph, CN, CH(CO,R),, OR, SR

represents an extremely versatile new route to iron-alkenyl complexes. An important aspect of this reaction is the stereochemistry of t h e addition.2 I n our earlier report, IH NOE enhancement experiments were used to assign the stereochemistry of the products isolated in these reaction^.^ With the exception of hydride as the n ~ c l e o p h i l e the ,~ trans configuration was assigned to the products as shown in eq 1. Of considerable importance is the fact t h a t de(1)Reger, D. L.; McElligott, P. J. J . Am. Chem. SOC. 1980,102,5923. (2) Trans addition of nucleophiles to [CpFe(C0)2(~2-alkene)]+ complexes has been previously demonstrated: (a) Nicholas, K. M.; Rosan, A. M. J. Organomet. Chem. 1975,84, 351. (b) Sanders, A.; Magatti, C. V.; Giering, W. P. J. Am. Chem. SOC.1974, 96,1610. (3) These NOE experiments have not proven to be readily reproducible for CpFeCO[P(OPh),](alkenyl) complexes. Slight decomposition of the complexes could place paramagnetic iron in solution. This would diminish the observed NOE enhancements. This point and other NMR methods for determining the stereochemistry of these iron-alkenyl complexes will be discussed in a later publication. (4) The structure of the product of the reaction of [CpFeCO(PPh3)(q*-MeC=CCO2Et)]BF, and L-Selectride, crystallized after purification on alumina, has been determined crystallographically. The added hydride is cis with respect to iron. Atwood, J. L.; personal communication.

0276-7333/83/2302-0101$01.50/0

M h

the E isomer, slowly isomerizes to an equilibrium mixture of the E and 2 isomers. A variety of experiments allowed the authors to propose that reaction 2 actually goes by cis addition, followed by a cis-trans isomerization. Thus, determination of the stereochemistry of the product of a reaction that produces a metalloalkenyl complex does not definitively establish the actual mode of addition. Others have proposed similar isomerization processes for other alkenylmetal complexes.6 We present here results, both synthetic and structural, that strongly support trans addition of methyl and phenyl substituents delivered from organocuprate reagents. These results include the solid-state structure of CpFeCO[P(OPh),[(Z)-C(Me)=C(Ph)Me], as determined by X-ray crystallography. We also show t h a t higher order mixed (5) Huggins, J. M.; Bergman, R. G. J. Am. Chem. SOC. 1981,103,3002. (6) (a) Green, M.; Norman, N. C.; Orpen, A. G. J. Am. Chem. SOC. 1981, 103, 1267. (b) Murray, T. F.; Norton, J. R. Ibid. 1979, 101, 4107 and references therein.

0 1983 American Chemical Society

102 Organometallics, Vol. 2, No. I , 1983 organocuprate reagents of the type R2Cu(CN)Li2 are particularly effective reagents in these reactions.

Experimental Section General Procedure. All operations on complexes in solution were carried out under an atmosphere of prepurified nitrogen using solvents that were purified and degassed before use. Infrared spectra were recorded on a Beckman Model IR 4210 spectrometer. Proton NMR spectra were recorded on a Varian Model EM 390 spectrometer and chemical shifts are reported as 6 vs. Me4Si. Carbon-13 spectra were recorded on a Varian CFT-20 spectrometer using CDC1, as the solvent and internal standard (G(CDC1,) 76.9). Alkyllithium reagents were purchased from Aldrich, CuCN from Fisher, and AgBF4 from Ozark-Mahoning. CpFeCO[P(OPh),]I was prepared by the method of Brown et ale8 Elemental analyses were performed by Robertson Laboratory. CpFeCO[P(OPh),][ (E)-C(Me)+( Me)Ph]. A mixture of CpFeCO[P(OPh),]I (1.64 g, 2.8 mmol) and AgBF4 (0.58 g, 3.0 mmol) was stirred in CH2C12(25 mL) at room temperature, and after 10 min M e C e M e (0.20 g, 0.30 mL, 3.7 mmol) was added. This solution was stirred for 40 min and filtered by using Celite. The solvent was evaporated, yielding a reddish brown fluffy solid. This solid was dissolved in THF (40 mL) prechilled to -78 "C and mixed with a cold THF solution of Ph,Cu(CN)Li2 (made by addition of PhLi (3.9 mL of 1.43 M solution, 5.6 mmol) to CuCN (0.25 g, 2.8 mmol) in the THF (20 mL) previously cooled to -60 OC). This mixture was stirred cold for 30 min and allowed to warm to ambient temperature, and the solvent was then evaporated to yield a green-brown oil. This oil was redissolved in CH,Cl, (20 mL) and filtered by using a short plug of alumina, followed by elution with an additional 40 mL of CHzCl2. Evaporation of the CHzClzyielded a yellow-orange oil (1.53 g, 93% based on CpFeCO[P(OPh),]I): 'H NMR (6 in CDCl,) 7.1 (20, m, P(OPh),, Ph), 4.33 (5, s, Cp), 2.20, 2.00 (3, 3; br s; Me's); IR spectrum (cm-' in hexane) v(C0) 1946; 13C NMR (6 in CDC13) 219.6 (d, J = 50.7 Hz, CO), 151.8, 129.5, 124.7, 121.8, (d, s, d, d; J = 10.4,0.8, 3.7 Hz; P(OPh),), 149.1 (d, J = 3.1 Hz, =C(Me)Ph), 141.4, 128.6, 127.8, 121.5 (all s, =CPh), 137.7 (d, J = 34.2 Hz, FeC=), 84.4 (d, J = 1.8 Hz, Cp), 36.1,29.7, (d, s; J = 4.9 Hz, Me's). Anal. Calcd for CgH3,FeO4P: C, 69.16; H, 5.29. Found: C, 68.85; H, 5.25. CpFeCO[P(OPh)3][(Z)-C(Me)=C(Ph)Me]. This complex was prepared in an manner similar to that outlined above by using MeCSCPh and MezCu(CN)Li2.The orange oil obtained after CH2Clzevaporation was dissolved in benzene (20 mL) and stirred with alumina (4 g). This mixture was filtered, followed by elution with benzene (20 mL), and the benzene evaporated (25 "C), yielding an orange oil (1.43 g, 87%): 'H NMR (6 in benzene-de) 7.3-6.7 (20, m, P(OPh),, Ph), 4.18 (5, s, Cp), 2.55, 2.23 (3, 3; s, s; Me's); IR spectrum (cm-' in hexane) v(C0) 1951; 13CNMR (6 in CDCl,) 217.4 (d, J = 49.1 Hz, CO), 151.4, 129.4, 124.5, 121.2 (d, s, s, d; J = 10.3, 4.2 Hz; P(OPh),), 152.4 (s,=C(Ph)Me), 142.1, 129.9, 126.9, 121.6 (all s, =CPh), 136.5 (d, J = 37.2 Hz, FeC=), 84.7 (s, Cp), 34.0, 23.8 (d, d; J = 9.1, 3.1 Hz; Me's). Anal. Calcd for C34H31Fe04P: C, 69.16; H, 5.29. Found: C, 68.90; H, 5.19. X-ray Data. Crystals of CpFeCO[P(OPh),] [ (2)-C(Me)=C(Ph)Me] were grown from hexane solution, isolated, and sealed into thin-walled capillaries and mounted on a CAD-4 diffractormeter interfaced to a PDP 11/40 computer. The crystal alignment, data collection techniques, computer programs, etc. used were those previously r e p ~ r t e d . ~The J ~ structure was solved by standard heavy-atom methods and refined by full-matrix least squares including anisotropic temperature factors to a final conventional R of 0.047 with 2545 observed reflections. For details see Table I. No attempt was made to locate the numerous hydrogen atoms, and they were not included in the refinement.

Reger et al. Table I. Cell Data, Data Collection, and Refinement Parameters for Cp FeCO [P( OPh, )][ ( Z )-C(Me )=C( Ph )Me] Cell Data a = 8.482 ( 3 ) A p(obsd) = 1 . 3 3 g/cm3 p(ca1cd) = 1.36 g/cm3 b = 36.84 (1)A fw 590.4 g/mol c = 9.939 ( 3 ) a z=4 p = 112.20 (3)O Data Collection wavelength Mo K a , h = 0.710 73 A graphite monochromator used, e = 6.1 space group P2,lc h01, 1 = 2n t 1;OkO, k = 2n + 1 absent size of crystal = 0.17 X 0 . 3 4 X 0.34 mm 1 = 6 . 4 cm-' faces of the form {OOl}, {110}, {OlO} absorption corrections made and maximum and minimum transmission factor found were 0 . 9 1 3 and 0.89614 P factor = 0 . 0 3 0 in u ( F o z )= [0(1,,,)~ t (P1,a,)z]1'2/Lp and w = ~ / U ( F , ) ~ data considered nonzero if F z > 4 u ( F Z ) , IF I > 14.0 8349 independent hkl's measured in W-28 mode; 47" < 2e < 60°, 4 0 0 0 measured F's, 4 5 0 f 0, 28 (max) = 6 0" 2545 reflections used t o solve and refine structure variable scan speed with preliminary scan speed of 4"/min ( 2 e ) 25 reflections used in orientation matrix (checked every 24 h) three standard reflections monitored every 1 0 0 reflections, decay less than 2% I room temp 18 "C Refinement Parameters structure refined by full-matrix least square^,'^ including anisotropic temperature factors and anomalous dispersion corrections with weights based upon intensity statistics, function minimized = x i w i [lFcl -- IFol]z largest shift a t end of refinement = 0.02 u final least squares performed on Amdahl V6 ( f ' s from international tables V.IV)15 no. of variables = 361 final R = 0.047, weighted R = 0 . 0 6 2 error of observn of unit weight = 2.05 A listing of structure factors is available as supplementary material. Table I1 contains the atomic positional and thermal parameters. Interatomic distances and angles are found in Table 111,and relevant dihedral angles and selected nonbonded distances are in Table IV. An ORTEP drawing of an individual molecule is shown in Figure 1. Figure 2 shows an ORTEP drawing of the unit cell contents.

Results and Discussion Two isomers of the formula CpFeCO[P(OPh),] [a-C(Me)=C(Me)Ph] can be prepared as shown in eq 3 and 4. The products of these reactions were clearly established

(7) Lipshutz, B. H.; Kozlowski, J.; Wilhelm, R. S. J.Am. Chem. SOC. 1982, 104, 2305.

(8) Brown, D. A,; Lyons, H. J.; Manning, A. R.; Rowley, J. M. Inorg. Chim. Acta 1969, 3, 346. (9) Griffith, E. A. H.; Charles, N. G.; Amma, E. L. Acta Crystallogr., Sect. B 1982, B38,262. (10) Reger, D. L.; McElligott, P. J.; Charles, N. G.; Griffith, E. A. H.; Amma, E. L. Organometallics 1982, I , 443.

by NMR ('H and 13C) spectroscopy to be different compounds of the basic structural type indicated. Of importance is t h e fact that these two compounds do not interconvert over a period of weeks in solution at room temperature and decompose above 90 OC. T h e structure of

q2-Alkyne Complexes of Iron

Organometallics, Vol. 2, No. 1, 1983 103

Table 11. Positional and Thermala Parameters and Their Estimated Deviations for CpFeCO[P( OPh),][(Z)-C(Me)=C(Ph)Me] atom

X

Fe P O(1) O( 2) O(3) O(4) C(1) C(1C) C(2C) C(3C) C(4C) C( 5C) C(lP2) C( 2P2) C(3P2) C(4P2) C(5P2) C(6P2) C(lP3) C( 2P3)

0.0900 (1) 0.2648 (2) 0.4150 ( 5 ) 0.1946 (5) 0.3838 (5) -0.0838 (8) -0.0113 (9) -0.125 (1) -0.124 (1) 0.029 (1) 0.121 (1) 0.024 (1) 0.0284 (8) -0.018 (1)

Y

2

0.35133 (2) 0.29792 (9) 0.39435 ( 4 ) 0.3391 (2) 0.3971 (1) 0.2764 (4) 0.4355 (1) 0.2980 (5) 0.3975 (1) 0.5078 (4) 0.3724 (2) -0.0014 (6) 0.3637 ( 2 ) 0.1157 (8) 0.307 (1) 0.3237 (2) 0.3615 (2) 0.3549 (9) 0.4783 (9) 0.3656 (2) 0.3326 (2) 0.5066 (9) 0.3989 (9) 0.3063 ( 2 ) 0.4467 (2) 0.2719 (7) 0.4562 (2) 0.3863 (8) -0.181 (1) 0.4689 ( 2 ) 0.358 (1) -0.297 (1) 0.4730 ( 3 ) 0.215 (1) -0.247 (1) 0.4638 (3) 0.103 (1) -0.082 (1) 0.4507 (2) 0.1289 (9) 0.5315 (8) 0.4188 (2) 0.5735 (7) 0.6858 (9) 0.4007 (2) 0.6240 (8)

B, A ’ 2.75 (3) 2.59 (7) 3.1 (2) 3.8 (2) 3.3 (2) 5.7 (3) 3.4 ( 3 ) 4.8 (4) 4.6 ( 4 ) 4.5 (4) 4.8 ( 4 ) 4.7 (3) 3.3 (3) 4.2 (3) 5.5 (5) 6.2 (5) 6.0 (5) 4.5 (3) 3.0 ( 3 ) 4.2 ( 3 )

atom C(3p3) C(4p3) C(5p3) C(6P3) C(lP1) C(2p1) C(3P1) C(4P1) C(5P1) C(6P1) C(1V) C(2V) C(3V) C(4V) C(lP4) C(2P4) C(3P4) C(4P4) C(5P4) C(6P4)

X

Y

z

B, A ’

0.833 (1) 0.822 (1) 0.667 (1) 0.5180 (9) 0.3885 (8) 0.456 (1) 0.448 (1) 0.370 (1) 0.305 (1) 0.312 (1) 0.2559 (8) 0.2290 (9) 0.364 (1) 0.4270 (9) 0.0640 (9) 0.054 (1) -0.097 (1) -0.243 (1) -0.232 (1) -0.0797 (9)

0.4206 (3) 0.4571 (3) 0.4750 ( 2 ) 0.4554 (2) 0.3971 (2) 0.3672 (3) 0.3683 (4) 0.3977 (4) 0.4269 (4) 0.4266 (3) 0.3168 (2) 0.2960 (2) 0.2699 (3) 0.3125 ( 2 ) 0.2937 (2) 0.3055 (2) 0.3038 (3) 0.2880 (3) 0.2760 (2) 0.2785 (2)

0.7038 (8) 0.7290 (8) 0.6757 (8) 0.5979 (8) 0.1281 (7) 0.0822 (9) -0.064 (1) -0.153 (1) -0.103 (1) 0.0411 (9) 0.2607 (7) 0.1432 (8) 0.127 (1) 0.3890 (8) 0.0138 (8) -0.1227 (8) -0.2432 (9) -0.2283 (9) -0.094 (1) 0.0272 (8)

4.6 ( 4 ) 4.6 ( 4 ) 4.7 (3) 3.8 (3) 3.6 ( 3 ) 5.3 (5) 7.3 (7) 7.2 ( 7 ) 7.3 ( 7 ) 5.1 (5) 3.2 (3) 4.0 (3) 6.8 (5) 4.5 (3) 3.7 (3) 4.7 (4) 5.6 (4) 5.2 (4) 5.0 (4) 4.0 (3)

atom U(1,1) U( 2,2) U( 393 1 U(1A WL3) U(2,3) Fe 0.0322 (4) 0.0367 (5) 0.0342 (4) -0.0036 (5) 0.0108 (4) -0.0019 (5) P 0.0316 (8) 0.0374 (9) 0.0290 (8) -0.0033 (7) 0.0113 (7) -0.0010 (7) 0.034 ( 2 ) 0.056 (3) -0.004 (2) 0.031 ( 2 ) -0.000 (2) 0.014 (2) O(1) 0.043 ( 3 j 0.036 ( 2 j 0.065 (3) 0.003 (2) 0.003 (2) 0.019 (2) O(2) 0.041 ( 2 ) 0.030 (2) 0.053 (3) -0.014 (2) -0.006 (2) 0.012 (2) (43) 0.092 (4) 0.053 (4) 0.010 (3) -0.004 (3) 0.002 (3) 0.045 (3) O(4) 0.049 (4) 0.026 (3) 0.004 (3) 0.014 (3) 0.049 (4) -0.004 (3) C(1) 0.060 ( 5 ) 0.063 (6) 0.048 (5) -0.020 (4) 0.078 ( 6 ) -0.011 (4) C( 1 C) 0.055 ( 5 ) 0.067 (6) -0.015 (4) 0.043 (4) 0.069 (5) -0.014 (4) C(2C) 0.054 ( 5 ) 0.073 (6) -0.014 (4) 0.037 (4) 0.058 (5) -0.010 (4) C(3C) 0.077 ( 6 ) 0.062 (6) -0.014 (5) 0.043 (4) 0.057 (5) 0.004 (4) C(4C) -0.014 (4) 0.034 (4) 0.064 ( 5 ) 0.063 ( 5 ) 0.061 (5) 0.012 (4) C(5C) 0.041 (4) 0.034 (4) C(1P2) -0.003 (3) -0.004 (3) 0.017 (3) 0.051 (4) C( 2P2) 0.030 (4) 0.060 (5) 0,009 (4) 0.055 (5) 0.051 (5) 0.000 (4) 0.047 (6) C(3P2) 0.090 (7) 0.074 ( 6 ) 0,009 (4) 0.060 (6) -0.002 (5) C( 4P2) 0.029 (6) 0.093 (7) -0.006 (6) 0.064 ( 6 ) 0.010 (5) 0.076 (7) 0.003 (5) C( 5P2) 0.050 ( 5 ) 0.084 (7) 0.014 (5) -0.002 (5) 0.077 (6) C( 6P2) 0.056 (5) -0.003 (4) 0.055 (5) 0.050 ( 4 ) 0.011 (4) 0.007 (4) 0.028 (3) C( 1P3) 0.040 ( 4 ) 0.045 (4) -0.007 (3) 0.013 (3) 0.000 (3) C( 2P3) 0.046 (4) 0.045 ( 4 ) 0.064 (5) 0.012 (3) -0.000 (4) 0.005 (4) C(3P3) 0.043 (4) 0.074 (6) 0.053 (5) 0.001 (4) 0.011 (4) -0.010 (4) C( 4P3) 0.079 (6) 0.035 (4) 0.058 ( 5 ) -0.023 (5) 0.013 (4) -0.003 (4) 0.044 (4) C( 5P3) 0.065 ( 5 ) 0.065 (5) 0.017 (4) -0.009 (4) -0.018 (4) C( 6P3) 0.047 (4) 0.052 ( 4 ) 0.044 (4) -0.006 (3) 0.016 (3) -0.010 (3) 0.070 (5) C( 1P1) 0.034 (3) 0.034 ( 3 ) -0.014 (3) 0.013 (3) -0.002 (4) C( 2P1) 0.060 (5) 0.062 ( 5 ) 0.095 ( 7 ) -0.031 (5) 0.039 (4) -0.028 (5) C( 3P1) 0.091 ( 7 ) 0.070 (6) 0.14 (1) -0.043 (7) 0.051 (6) -0.033 (7) C( 4P1) 0.054 (6) -0.036 (7) 0.031 (5) 0.067 ( 6 ) 0.16 (1) 0.001 (7) 0.053 ( 6 ) C( 5P1) 0.058 ( 6 ) -0.014 (6) 0.17 (1) 0.023 (5) 0.026 (7) 0.096 (7) C(6P1) 0.051 (5) 0.044 ( 4 ) -0.010 (4) 0.016 (4) 0.022 (4) 0.043 (4) 0.037 (4) 0.037 (4) 0.005 (3) 0.011 (3) -0.000 (3) C(1V) 0.051 ( 4 ) 0.040 (4) 0.055 (5) 0.013 (3) 0.005 (3) -0.012 (4) C( 2V) 0.064 (6) 0.084 (7) 0.099 (7) 0.028 (5) 0.020 (5) -0.039 (6) C(3V) 0.040 (4) 0.055 (5) 0.053 (4) 0.011 (4) -0.008 (3) 0.005 (4) C(4V) C( 1P4) 0.047 (4) 0.039 (4) 0.000 (3) 0.015 (3) 0.051 (4) -0.010 (3) 0.065 (6) 0.060 ( 5 ) C( 2P4) 0.022 (4) -0.007 (4) 0.053 (5) -0.010 (4) C(3P4) 0.077 (6) 0.077 (6) 0.021 (5) -0.011 (5) 0.054 (5) -0.009 (4) C(4P4) 0.073 (6) 0.061 ( 5 ) 0.008 (4) -0.007 (4) 0.052 (5) -0.013 (4) C(5P4) 0.056 (5) 0.059 (6) 0.067 (6) 0.013 ( 4 ) -0.012 (4) -0.010 ( 4 ) 0.042 (4) 0.046 (4) C(6P4) 0.058 ( 5 ) 0.014 (3) -0.007 (3) -0.014 (3) a The form of the anisotropic thermal parameter is exp(-an2( U( l , l ) h 2 a 2+ U(2,2)k2bzt U(3,3)12c2+ 2U( l,2)hkab cos y t 2U(1,3)hZac cos p + 2U(2,3)kZbc cos a)).

the Z isomer formed in reaction 4 has been definitively established by a single-crystal X-ray structural determination. The structure may be described as isolated molecules, Figure 1,separated by ordinary van der Waals distances, Figure 2. Figure 1 shows an ORTEP drawing of the molecule, establishing both the regio- and stereochemical consequences of reaction 4. The nucleophile adds to the alkyne carbon atom bearing the phenyl substituent. The same regiochemistry is observed with similar $-styrene

derivatives.ll I t is clear that the Fe atom and the phenyl group are on the same side of the ethylene linkage, thus establishing the complex as the Z isomer. If the center of the Cp ring is considered a coordination site, the local geometry about the Fe atom is that of a distorted tetrahedron. As expected, the Cp(center)-Fe-L, where L = C(lV), P, or C ( l ) , angles of 119.5 (5)-126.0 (5)’ are greater (11) Lennon, P.; Rosan, A. M.; Rosenblum, M. J. Am. Chem. SOC. 1977, 99, 8426.

104 Organometallics, Vol. 2, No. 1, 1983

Reger et al.

Table 111. Bonded Distances (A) and Angles (Des) with Esd's in Parentheses for CpFeCO[P(OPh),lt(Z>C(Me)=C(Ph)Mel Bond Distances Fe-P OI11-CIlP11 1.404 IX) CI3P21-CI4P2) 1.40 (1) Z.lOZ(2) Fe-C(l) 1.746 (7) oizj-c(ipz) i.396 (Sj C ( ~ P Z ) - C ~ j~ P Z 1.37 izj Fe-C(1V) 2.031 (8) O( 3)-C( 1P3) 1.411 (8) .C(5PZ)-C(6P2) 1.40 (1) Fe-C(1C) 2.12 (1) C( 1C)-C( 2C) 1.384 (9) 1.47 (1) C(6P2)-C( 1P2) 2.13 (1) C(lP3)-C(ZP3) C(ZC)-C(3C) 1.38 (1) Fe-C(2C) 1.42 (1) Fe-C(3C) 2.11 (1) 1.40 (1) C(ZP3)-C(3P3) C(3C)-C(4C) 1.41 (1) Fe-C(4C) 2.107 (9) 1.45 (1) 1.38 (1) C(3P3)-C(4P3) C(4C)-C(5C) Fe-C(5C) 2.120 (9) 1.40 (1) 1.39 (1) C(4P3)-C(5P3) C(5C)-C(lC) Fe-center ' 1.736 (9) C(lP1 \-CIZPl) 1.39 (1) CI 5P3)-C(6P3 \ 1.41 (1) 1.138 (9) cizpii-ci3pii 1.43 i z i Ci6P3i-Ci 1P3i 1.38 i i i c(1)-0(4) c i 3 p i j - c i 4 ~ 1j C(lV)-C(4V) 1.536 ( 8 ) i.40 izj 1.40 i i j C( 1V)-C( 2V) 1.34 (1) C(4Pl)-C(5Pl) 1.39 (2) 1.38 (1) C( ZV)-C(SV) 1.55 (1) C( 5Pl)-C(6Pl) 1.41 (1) 1.42 (1) C(2V)-C(lP4) 1.39 (1) 1.37 (1) 1.503 (9) C( 6Pl)-C( 1P1) P-O(l) C( lP2)-C(ZP2) 1.40 (1) 1.38 (1) 1.619 (5) P-0(2) 1.38 (1) 1.39 (1) C( ZPZ)-C(3P2) 1.623 (5) 1.602 ( 4 ) P-0(3) Bond Angles P-Fe-C( 1) C(3V)-C(2V)-C(lP4) C( lPZ)-C( 2PZ)-C(3PZ) 119.5 (7) 92.3 (2) 111.3 (7) P-Fe-C(1V) Fe-CI 1\-0I4) CI2P21-CI3P21-C14P2 I 120 (1) 91.2 (2) 176.6 (8) P-Fe-centera 119.1 (9) 126.0 ( 5 ) 109.3 (7) C( 1)-Fe-C( 1V) 94.5 (3) 121.5 (8) 105.7 (7) C( 1)-Fe-center" 124.5 (5) 117.9 (9) 109.5 (7) C( 1V)-Fe-center" 119.5 (5) 122.4 (6) 108.4 (6) Fe-P-O( 1) 124.9 (2) 118.1 (7) 107.1 (7) Fe-P-O(2) 119.4 (2) 120.5 ( 7 ) 124.5 (4) Fe-P-0(3) 112.2 (2) 120.8 (7) 124.8 (4) O(l)-P-0(2) 96.4 (3) 119.4 (8) 128.5 (4) 118.8 ( 7 ) 97.0 (2) 124.5 (8) 102.8 ( 2 ) 116.3 (8) 118.8 ( 6 ) 114.6 (5) 121.7 (9) 120.( 1) 127.9 (5) 119.0 (9) 122.(1) 117.4 (6) 119.4 ( 7 ) 119.(1) 123.6 (6) ~ ( 4 j -~c (45 ~ 4j - c ( 6 ~ 4j 118.2 (9) 121.0 (9) 125.0 (7) 121.5(7) C(5P4)-C(6P4)-C(lP4) 120.2 (8) a Center of cyclopentadiene ring. Esd's are approximate. ~~

-\--I

C(2V), C(3V), C(4V), C(lP4) Angles between Planes, Deg IV-VI 67.3 (1) [center*, Fe, C(l)]-VI V-VI 31.1 (1) VI-[C(lV), Fe,PI Nonhonded Distances, A C(4V)-C(4C) 3.31 (1) C(2P4)-0(4) C(4V\-C15C\ 3.46 (1) C(6P4)-C(lC)

~I

~~~

~I

0.009 (3) 0.010(3) 0.008 (3) 0.012 (3) 0.003 (3) 0.05 (1) 59.3 (1) 55.4 (1) 3.15 (1) 3.39 (1) 3.39 (1)

than the tetrahedral angle, whereas the L F e L angles are 91.2 (2)-94.5 (3)' (Table 111). T h e P-0 distances are essentially equal and are less than three standard deviations from the average of 1.614 A. T h e Fe-C(lV) distance of 2.031 (8) A is almost identical with t h a t observed by us recently in a similar compound'0 and is indicative of an Fe-C single bond to an sp2-bybridized carbon. In general, the bond distances and angles and nonbonded interactions, both inter- and intramolecular, are normal. T h e orientation of the alkenyl moiety is determined by nonbonded repulsions between the Cp ring and the C(4V) methyl group of the alkene, see distances of C(4V)-C(4C) and C(4V)