Inorganic Chemistry
948 NOTES
TABLE I (CN)B~-,M O ( C ~ O ~ )and ~ ~ -M , O ( C O ~ ) J ~ -Each . PHOSPHORUS AND PROTON N M.R. ABSORPTIONS has been shown to be diamagnetic, indicative of ComJP-0-0-H 6(Hl)d d 4sp bonding . l W g pound 6(Pa*) (c.P.s.) Cp CYe c8 The physical properties of MoCI~.~(CF~H&ASO I -91.5Q 2 3.93 0.72 suggest that it is the first example of a neutral I1 -57.4" 6 4.48 .87 I11 +7.97O 7 4.48 .90 octacoordinate Mo(1V) complex, Uncomplexed 3.03,1.87 IV -137"~' 6 4.32 MoClp is extremely sensitive to oxidation and v -64.0' 19 4.97 2.73,1.85 hydrolysis, but the present complex is unaffected VI +10.4' 20 5.08 2 . 8 2 , l . S by boiling in water for 15 min., and by subsequent a In chloroform. In acetonitrile. ' In dimethyl sulfprolonged standing in water a t room temperature. oxide. Greek subscripts refer to the position of the MoC1, is highly colored; the complex is white. proton-bearing carbon atom with respect t o phosphorus. The difference in the chemical shifts of these protons is The presence of eight ligands, coupled with the due to the chemically different axial and equatorial posiconductance data, can only be accounted for by tions they occupy. octacoordination.
Acknowledgment.-This work was supported in part by the Office of Naval Research. (7) M. C. Steele, A u s t d i a % J . Chem., 10, 367, 3G8 (1967). (8) P. Ray and H. Bbar, J . I n d i a n Chem. Soc., 6, 497 (1928). (9) W. Klemm and H. Steinberg, 2. anorg. allgem. Chem., 227,
193 (1936).
DEPARTMENT OF CHEMISTRY, IOWASTATE UXIVERSITY, AXES, IOWA
CONTRIBUTION FROM THE
"C-H
Phosphorus Nuclear Magnetic Resonance Spectra of Polycyclic Phosphorus Compounds BY J. G. VERKADEAND R. W. KING
Received June 8, 1962
The chemical shifts of phosphorus in the polycyclic compounds 1-111' and TV-VL2 have been investigated. To ensure adequate signal strength, phosphorus spectra were obtained a t 24.3 Mc./sec. on a t least 1 M solutions. Where different solvents were used for the same compound, no significant difference in shift was observed. 3,4 Phosphorus chemical shifts are recorded in Table I in p.p.m. from external 85% phosphoric acid. The positive and negative signs refer to upfield and downfield values, respectively. Proton shifts were measured at 60 Nc./sec. and are recorded in p.psn. down(1) J. G. Verkade and L. T. Reynolds, J . Org. Chem., 26, 663 (1960). Compound names: 4-methyl-2,6,7-trioxa-l-phosphabicyclo[2.2.2loctane (I), its 1-sulfide (111, and 1-oxide (111). (2) H. Stetter and K . Steinancker, Bey., 86, 451 (1952). Com2,8,9-trioxa-1-phospha-adamantane(IV), its 1pound names: sulfide (V), and 1-oxide (VI). (3) R. A. Y. Jones and A. R. Katritzky, Angew. Chem , 1, 32 (19 62). (4) N. Muller, P. Lauterbur, and J. Goldenson, J , A m . Chem. Soc , 78. 3557 (1868).
A
I
H
( I ) (X = none) (11) (X = sulfur) (111) (X = oxygen)
(IV) (X = none) ( V ) (X = sulfur) (VI) (X = oxygen) Figure 1.
field from tetramethylsilane in deuteriochloroform solutions a t least 5% by weight in polycyclic compound. Theoretically, the threefold axial symmetry of these molecules requires that phosphorus coupling with the nearest hydrogen atoms in the molecule yield a PS1septet in compounds 1-111 and a quartet in compounds IV-VI. The theoretical number of peaks was observed in the spectra of compounds IV-VI but spectra of compounds I111 revealed only five peaks; the outer two of theoretical intensity 5% of that of the center peak being lost in the noise. Phosphorus-proton coupling constants, JP-0-C-H, obtained from H1resonance spectra, were substantiated by values obtained from P3I resonance spectra. The only H' spectrum which did not afford a value for this coupling was that of compound IV where the more complicated proton-proton coupling caused broadening of the absorptions so that the relatively small phosphorus-proton coupling was unobservable. The value for this constant was ob-
VoZ. 1, No. 4 , November, 1962
NOTES 949
tained only from the P31spectrum. It is interestshould more purely be due to the formation of the ing that a change in the dihedral angle formed by phosphorus to electron-acceptor bond. the P-0-C-H bonds from 180' in compounds J. G. V. thanks the National Science Foundation for a grant for the P31rf. unit and matching IV-VI to 60' in the staggered configuration of probe. We thank Mr. Thomas J. Huttemann for compounds 1-111 causes a decrease in coupling constant by a factor of about three in the corsome of the experimental work. responding phosphites (I, IV) , phosphates (111, VI), and thiophosphates (11, V). A similar relation for H-C-C-H systems has been treated by CONTRIBUTION FROM THE DIVISIONOF CHEMICAL K a r p l u ~ . ~The increase in the value of JP-0-C-H DEVELOPMENT, TENNESSEE VALLEYAUTHORITY, for the series of compounds 1-111 and IV-VI is in WILSON DAM,ALABAMA accordance with the expectation that coupling is enhanced by increasingly electronegative subCrystallography of the Calcium stituents on the phosphorus atom. .Potassium Phosphate CaK,H(PO,), Phosphorus chemical shifts in trivalent phosphorus compounds have been related with some BY A. WILLIAMFRAZIER, JAMES P. SMITH, success to X-P-X bond angles (X = H or halogen) JAMES R. LEHR,AND WALTER E. BROWN by a consideration of the difference in electronegativity between X and P and the valenceReceived February 17, 1962 electron imbalance on p h o s p h o r ~ s . ~It~ ~would seem that the relatively large difference (45 The crystallographic properties of the nev salt p.p.m.) in P3l chemical shift of the phosphites (I, CaK3H(PO& and some of the properties of the IV) might be an indication of appreciably difpreviously known' salt MgNa3H(PO& were ferent 0-P-0 bond angles. Calculations based determined by petrographic and X-ray techon the method of Parks,6 however, yield 0-P-0 niques. bond angles differing by less than 1'. This method involves solution of a quadratic equation giving Experimental alternative 0-P-0 bond angles of 93' 1' and 104' Preparation of Crystals.-To a solution containing 115 g. 3l'for phosphite (I) and 93' 22' and 103' 59' for of KzHPO4 and 10 g. of KOH in 144 ml. of H2O was slowly phosphite (IV). On the basis of scale models, the added 50 ml. of 0.3 M calcium acetate. Rapid stirring latter of the two values for each molecule is the during the addition promoted formation of a uniform, well more plausible. X-Ray analyses of these comdispersed gel, which crystallized after standing 1 to 3 hr. at room temperature. The crystals were collected on a sucpounds and a number of metal complexes are in tion filter, washed several times with small volumes of progress to explore 0-P-0 bond angles and their water, once with acetone, and dried at 105". Anal. possible changes on coordination. The general Calcd. for CaKsH(P04)2: Ca, 11.51; K , 33.67; P, 17.78; trend in P3I chemical shifts from the trivalent HzO, 2.59. Found: Ca, 11.64; K, 33.5; P, 17.59; H20, phosphorus compounds (I, IV) to their corre3.02. The crystals decompose slowly in water to form apatite pseudomorphs. sponding pentavalent thiophosphate and phosMgNasH( PO& was prepared by the method of Bassett phate derivatives parallels that observed for and Bedwell.' Anal. Calcd. for MgNa~H(P04)2: Mg, (C2H00)3P, (C2Hs0)3PS, and (CzHs0)3PO.' 8.56; Na, 24.26; P, 21.79; H20, 3.17. Found: Mg, 8.4; In contrast to acyclic compounds of comparable Na, 23.5; P, 21.6; H20, 4.9. molecular weight, the rigidity of the polycyclic phosphites (I, IV) will minimize changes in O-PResults 0 bond angle, conformational changes, and steric Morphological and Optical Properties.-The hindrance upon coordination to the chalcogens as salt CaKgH(PO& crystallizes as plates having well as to transition metalss and group I11 acidsg monoclinic holohedral symmetry, class 2/m. The Hence the change in P3Iresonance on coordination crystals are tabular on (001), which is also the composition plane of polysynthetic twins. Modifying ( 5 ) M. Karplus, J . Chem. Phys., 30, 11 (1959). forms, the sets { 111f and { 201 f , impart a pro(6) J. R. Parks, J . A m . Chem. SOL, 79, 757 (1957). (7) J. A. Pople, W. G. Schneider, and H. J. Bernstein, "Highnounced pseudo-hexagonal symmetry to the resolution Nuclear Magnetic Resonance," McGraw-Hill Book Complate crystals and make them resemble truncated pany, Inc.. New York, N. Y.,1959, p. 348. (8) J. G. Verkade and T. S. Piper, Inovg. Chem., 1, 453 (1962). (9) C. W.Heitsch and J. G. Verkade, ibid., 1, 392 (1962).
(1) H.Bsssett and W. I,. Bedwell, 1.Chem. Sor., 877 (1933).
