Preparation of hydridonickel phosphites - Inorganic Chemistry (ACS

Bicyclic Phosphite Esters from Pentaerythritol and Dipentaerythritol: New Bridging ... and crystal structure of a cationic nickel nitrosyl bicyclic ph...
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2800 Inorganic Chemistry, Vol. 13, No. 12, 1974

Verkade, et SI. Contribution Oorn Gilman Hall, Iowa State University, Ames, Iowa 50010

Preparation of Hydridonickel G. K. McEWEN, C. J. RIX, M. F. TRAYNOR,' and J. G. VEKKADE* Received June 3, 19 74

AIC40354D

Direct protonation of Ni(phosphite), compounds containing acyclic, monocyclic, and bicyclic phosphite ligands has been achieved using H,SO,, CF,COOH, and FS0,H. The pale yellow solutions, containing BNi(phosphite),* species, are extremely air sensitive and thermally decompose even at room temperature; hence these hydrido complexes have only been characterized in solution using a combination of ' H and 31 P nmr spectroscopy. However, protonation of a tetrakis(bicyc1ic phosphite)nickel(O) derivative with HCl, HBF,, or HPF, has led to the isolation of solid hydridonickel phosphite complexes of the type HNi(bicyc1ic phosphite),*X- (X = HCl,-, BF,-, PF;). The cream powders are stable for many days at room temperature under vacuum and they have been identified by both analysis and it spectroscopy. Further characteriiation was not possible since the compounds were not soluble in any common solvents. The variation in the ease of protonation of the Ni(phosphite), derivatives and the trend in P-H coupling constants in the HNi(phosphite), ' species suggested that the basicity order of the Ni(phosphite), complexes, and hence the basicity of the coordinated phosphite ligands, is acyclic > monocyclic > bicyclic. An ir study of the corresponding Ni(CO), (phosphite) derivatives suppoited this sequence.

Introduction Recently, Schunn2 succeeded in preparing hydrido complexes by direct protonation of zerovalent nickel phosphine species. Drinkard3 and more recently Tolman4 have applied this procedure to the preparation of acyclic phosphite derivatives, and although they were unable to isolate any solid compounds, they did obtain spectroscopic evidence for the formation of hydrido moieties according to the equation Ni[P(OC,H,),],

H,SO,

ether

--+ HNi[P(OC,H,),]

,"HSO,-

(1)

The present work describes the preparation of hydridonickel complexes containing the constrained phosphites 1 and 2. Me I P; bicyclic. This sequence has recently been suggested by one of usI6 where it was rationalized in terms of changes in hybridization at the phosphite oxygen stemming from molecular constraint ~

Acknowledgments. We thank the National Science Foundation for a generous grant in support of this work and Mr. N. S. Morales for considerable assistance in obtaining the Fourier transform nmr spectra. Registry No. HNi(P(OEt),),+CF,COQ -,25512-94-1 ; HNi(l), 'HSO,-, 52699-29-3; HNi(l),'CF,COO~~,52731-26-7; HNi(Za),+CF,COO-, 52699-31-7; HNi(Za),+SO,F-, 52699-32-8; HNi(Zb),'CF,COO-, 52699-34-0; HNi(Zb),"SO,F-, 52699-35-1; N i ( l ) 4 , 52748-206; Ni(2a),, 14730-03-1; Ni(%b),, 52731-25-6; 2b, 52698-99-4; HNi(Za),+HCl;, 52699-36-2; HNi(2a),+BF4-,52699-37-3; HNi(2a),+PF6-, 52699-39-5; Ni(C0) (I), 5 2699-40-8. (16) J. 6. Verkade, Bioinorg. Ckem., 3, 165 (1974).

Contribution from the Department of Chemistry, Texas Christian University, Fort Worth, Texas 70129

Displacement Reactions on Donor-Haloalanes. Some Novel Chelated Aminedihydroaluminum(1+) Salts KENNETH R. SKILLERN and HENRY C. KELLY* ReceivedMay 31, 1974

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Iodide salts of two novel four-coordinate aluminum cations N,N,N',N'-tetramethylethylenediaminedihydroaluminum( 1+) and sparteinedihydroaluminum(1+) have been prepared by nucleophilic displacement reactions on trimethylamine-iodoalane and characterized b y infrared absorption and conductivity measurements. Trimethylamine-bromoiodoalane has been prepared along with N,N,N'J'-tetramethylethylenediamine complexes of AlH,Br and AlHBr, . The reaction with the monobromoalane yields the bromide salt of the chelated aluminum(l+) ion, while with the dibromoalane, the product appears to be a molecular complex containing five-coordinate aluminum.

Introduction The preparation and characterization of electrolytes containing four-coordinate boron cations of the type LL'BH2+ where L and L ' denote neutral electron-donor molecules have been d e ~ c r i b e d , 'and ~ ~ although numerous four-coordinate aluminum salts have been ~ r e p a r e d , ~analogous -~ dihydro (1) S. G. Shore and R. W. Parry, J. Amer. Chem. Soc., 8 0 , 8 (19 5 8). (2) N. E. Miller and E. L. Muetterties, J. Amer. Chem. SOC., 8 6 , 1033 (1964). (3) K. C. Nainan and G. E. Ryschkewitsch, J. Amer. Chem. SOC., 91, 330 (1969). (4) G. L. Smith and H. C. Kelly, Inorg. Chem., 8 , 2 0 0 0 (1969). ( 5 ) J. K. Gilbert and J. D. Smith,J. Chem. SOC.A , 2 3 3 (1968). ( 6 ) W. Wolfsberger and H. Schmidbaur, J . Organometal. Chem., 2 7 , 181 (1971). (7) J. Y . Corey and R. Lamberg, Inorg. Nucl. Chem. Lett., 8 , 275 (1972).

L2AlH2+species have not been reported. We have employed a method similar to one utilized in the synthesis of dihydroboron cations,899involving the reaction of trimethylamineiodoalane with the bidentate nitrogen bases N,N,N',N'-tetramethylethylenediamine (TMED) and sparteine t o prepare, via nucleophilic displacement of iodide ion and transamination, salts containing the corresponding chelated aminedihydroaluminum(l+) ions. Reactions of TMED with (CH3)3N. AlH2Br and (CH3)3N.AlHBr2 respectively, lead to a species which in solution appears to correspond t o the bromide salt of the TMED-AlH2+ ion and to a chelated complex which may contain five-coordinate aluminum. ~

(8) H. Noth and H. Beyer, Chem. Ber., 93, 2251 (1960). (9) J. E. Douglass,J. Amer. Chem. Sac., 8 6 , 5431 (1964).