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Permetalated Methyl Isocyanide.

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On crystallization of arsenic chalcogenide iodide glasses,
particular importance attaches to the metastable ternary pphases (Table 1). Thus, e. g., in each case the ternary crystalline phase initially formed during the ordering processes on
thermal treatment of glasses of the As2Te3-As13section is
the cubic (metastable) P-AST~I[’~.
In this crystal structure
(AB-type, fcc) tellurium and iodine are randomly distributed
at positions of a partial lattice, while the As partial latticelikewise random-is only 50% occupied. In the course of
further ordering (annealing; P-AsTeI --t a-AsTeI) the randomly semi-occupied As positions separate into ordered vacancies and fully-occupied lattice sites parallel to the (11 1)
faces of the cubic system and thus contribute to approximation to the structural assembly of the monoclinic thermodynamically stable a-AsTeI. The As-(Te,I) distance of 2.895
in P-AsTeI is 0: the same order of magnitude as the averaged value 2.915 A for all As-(Te,I) bond lengths of the rnacromolecular (ordered) structural element of a-AsTeI. Similar structural and phase relationships can be expected for aAsSeI and P-AsSeIllo1;a metastable AsSI phase has not been
observed by us.
ever, these main group metal-organic isocyanides in general
are poorly characterized, occurring only at low temperatures
and in low concentrations, respectively.
We now present a stable transition metal derivative ( I ) , in
which the CNC-skeleton functions as a pq-bridge between a
chromium atom and three cobalt atoms.
Compound ( I ) , which can be synthesized in 24% yield
from Cr(CO),CNCC13[31and C O ~ ( C O(molar
ratio 4:9) is
of interest for at least two reasons: (i) as the first functional
isocyanide with an a-acetylenic C-atom, and (zi) as the first
nonacarbonyltricobalt cluster containing a functional nitrogen-grouping on the methylidyne C - a t ~ m l ~ ~ .
Received: October 29. 1980 [Z 698 IE]
German version: Angew. Chem. 93, 218 (1981)
[ I ] Review: J. Fenner. A. Rabenau, C Trageser, Adv. Inorg. Chem Radiochem.
23, 329 (1980).
121 a) E. Dbnges, 2. Anorg. Allg. Chem. 263, 112 (1950); b) M. E. Lines,A . M.
Glass: Principles and Applications of Ferroelectrics and Related Materials.
Clarendon Press, Oxford 1977, p. 5 13.
131 a) The X-ray powder diagram of a-AsTeI is identical with fhat for a phase
reported as AsxTelIs cf. A. P. Chernou. S. A . Demboirskii, N . P Lurhnaya,
Zh. Neorg. Khim. 20, 2174(1975); b) A. P. Chernou, S. A . Dembouskii, I. A .
Kirilenko, Izv. Akad. Nauk SSSR, Neorg. Mater. 6,262 (1970; L. M . Agamirova, E. G. Zhukou, V. T. Kalinnikou. Russ. J. Inorg. Chem. 24. 1430
141 a) A. Rabenau, H. Rau, Inorg. Synth. 14, 160 (1973); b) by reducing the
amount of solid used (“AsxTe71c) by 80%. and under otherwise the same
conditions, a hitherto unknown tellurium subiodide [cf. R. Kniep, D. Mootr.
A . Ro6enau. 2.Anorg. Allg. Chem. 422, 17 (1976)] of the composition TeJ
was obtained in almost quantitative yield.
[5] N. Tarugi,Gazz. Chim. Ital. 27. 153 (1897).
[6] Elemental structure: P. Cherin, P. Unger, Inorg. Chem. 6. 1589 (1967).
[7] The occurrence of a chemically not fully Characterized cubic fcc-phase
on crystallization of Ass,,Te5,,. ,I, glasses ( ~ 5 3 7 has
) also
been described [R. K. Quinn, R. T. Johnson. J. Non-Cryst. Solids 7. 53
(1972)J. An fa-phase (a=5.782 A) identified by X-ray powder methods is
characterized as As6Tes12in [3a] (see, on the other hand, the data In Table
As expected, the IR spectrum of (1) consists of the v(C0)
pattern of the CO,(CO)~and Cr(CO)5 moieties (cyclohexane:
2110 vw, 2062 s, 2044 m, 1980 s, 1969 vs, 1945 vs cm-’)
which presumably masks the weak intensity v(CN) band. In
the mass spectrum of ( I ) the molecular ion and all CO-deficient molecular fragments down to the base peak of CO-free
[CrCNCCo3J’ appear as 15 equidistant groups of lines.
According to X-ray structure analysisf5J,the molecule in
the solid state has a crystallographic plane of symmetry
which contains 13 of the total of 35 atoms (Fig. 1). The structural dimensions in the CCO,(CO)~cluster compare well with
those reported for other representatives of this cluster familyi6’. In the Cr(CO), moiety, the trans CO ligand with
d(Cr-C11)= 1.860(4) and d(Cll-Oli)= 1.159(6) A as
1.140(6) reagainst d(Cr-C,,> = 1.892(9) and d(C-O),,=
flects the trans-influence of a typical C-isocyanide, having a
linear structure (CNC angle = 176.0(3), CrCN = 177.7(3)”).
181 AS-~,,,,,.,,
in AsI, = 2.591 A: R. Enjulberr, J. Galy, Acta Crystallogr. B 36.
914 (1980).
191 L. Pauling: The Nature of the Chemical Bond, 3rd Ed. Cornell University
Press, Ithaca, N. Y. 1960.
[lo] Note added in pro08 In the meantime a crystal structure analysis of AsSeI
has been published whose accuracy is comparable with the analysis described here for a-AsSeI: A. S. Kanishcheua, Yu. N . Mikhailkov, A . P. Chernow, Sov. Phys. Dokl. 25, 234 (1980).
Permetaiated Methyl Isocyanidel**]
By Wolf Peter Fehlhammer, Fritz Degel,
and Heribert Stolzenberg‘*J
a-Metalated isocyanides such as M-CX(H)-NC
(X = H,
C02R, S02aryl; M=Li,Na,Cu) have recently become important as versatile synthons in preparative organic chemistry[’’.
Except for the silylated species H3- ,,(SiR3),,CNCrZJ,
Prof. Dr. W. P. Fehlhammer. Dip[.-Chem. F Degel,
DiplLChem. H. Stolzenberg
Institut fur Anorganische Chemie der Universitat Erlangen-Nurnberg
Egerlandstrasse I. D-8520 Erlangcn (Germany)
Metal Complexes of Functional Isocyanides, Part 5. This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie. We thank Bayer AG for supplying the isocyanide dlchloride.-Part 4: [7a].
0 Verlag Chemie, CmbH, 6940 Weinheim, 1981
Fig. 1. ORTEP diagram of (CO)sCrCNCCo,(CO)9 (/) showing 3016 probability
ellipsoids 151.
A normal C=N bond length (1.160(5) A) coupled with a
markedly short N-C6 bond (1.354(5) A), however, clearly
demonstrates the sp character of the methylidyne C-atom.
Particular attention has been paid to the X-ray structural
assessment of the isocyanide nature of (I), since we had observed isocyanide-t cyanide isomerization in a number of
Angew. Chem. Inf. Ed. Engl. 20 (1981) No. 2
cases, even under very mild conditions[’]. Least-squares refinement calculations on the isocyanide and cyanide isomers
and a comparison of their thermal parameters, however, left
no doubt as to the correctness of the assignment.
The perchlorinated trichloromethyl isocyanide dichloride
(2)[’*l would appear to provide a direct entry to metal-rich,
CNC-bridged systems such as (1). Indeed, it reacts with excess C O ~ ( C O immediately
and cleanly to give ( 3 4 , but
there is no further reaction. The much higher reactivity of
the chlorine atoms in the a-position with respect to the isocyanide dichloride function thus is also established for reactions with organometallic nuc1eophilesfx1.Attempted dehalogenation by conventional methods[’[ of (3a) to give the parent isocyanide has so far failed. “Oxidative three-fragment
under very mild conaddition” of ( 3 4 to Pt(q2-C2H4)(PPh3)2
ditions yields a second permetalated methyl isocyanide species (4) exhibiting a weak IR absorption at 2170 cm-‘
[v(CN)][“’].On reaction with Pt(PPh,),, on the other hand,
(3a) only undergoes substitution to give (36).
temperature chlorination of tetramethylethylenediamine or
Received: August 18, 1980 [Z 691 IE]
German version: Angew Chem. Y3. 184 (1981)
CAS Registry numbers:
( I ) , 76346-71-9; (2). 29164-55-4 (30). 76346-72-0; (36). 76346-73-1; (4).7634674-2; (SJ. 29164-57-6. C r ( C 0 ) K N C C I J . 68927-87-7; Co2(CO),. 10210-68-1;
Pt(T2-C2H4)(PPh+, I21 20-1 5 - 9 Fe2(CO)*, 15321-51 -4
[ I ] a ) U. Schollkopf, Angew. Chem. 82. 795 (1970): Angew. Chem. Int. Ed.
Engl. 9, 763 (1970); Pure Appl. Chem. 51, 1347 (1979); D Hoppe. Angew.
Chem 86.878 (1974); Angew Chem. Int. Ed. Engl. 13. 789 (1974); T Saegusa, Y 110. Synthesis 1975. 291; b) A. M. van Leusen, J. Wildeman. U. H.
Uldenziel. J. Org. Chem. 42, 1153, 31 14 (1977): Synthesis IY77. 501.
121 R Wesr. G. A. Gornowicr, J. Organomet. Chem. 25, 385 (1970)
13) W P. Fehlhammer. F Degel, Angew. Chem. 91. 80 (1979); Angew. Chem
Int. Ed. Engl. 18, 75 (1979).
dimethylamino derivatives C O ~ ( C O ) ~ C N ( C H ~and
(41 Only
have previously been mentioned: D. Seyferrrh. I.
E. Hallgren. P. L K. Hung. J. Organomel. Chern. SO. 265 (1973).
I51 Monoclinic. P2,/m, Z=2. a = I1.683(5), b= 10.919(8). c=8.997(6)
p = 89.70(3)”. Philips PW 1100 automated four-circle diffractometer,
A&,. radiation (0.5614 A). 1701 independent reflections, R = 3.51%
(R, = 3.41%).
161 D. C. Miller. R. C. Gearhart. T. B. Brill. J. Organomet. Chem 169, 395
(1979). and references cited therein.
17) a) B. Weinberger. W. P. Fehlhammer. Angew. Chem. 92.478 (1980): Angew.
Chem. Int. Ed. Engl. 19. 480 (1980); b) E Beck, Dissertation. Universitat
Erlangen-Nhrn berg 1980.
181 a ) H Holrschmidr, E. Degener, H:G. Schmelzer. H. Tarnow. W Zecher. Angew. Chem. 74. 848 (1962). 80.942 (1968). Angew. Chem. Int. Ed. Engl. 1.
632(1962); 7.856(1968); b) E. Kuhle.ibid. X I . 18(1969)and8, 20(1969).respectively.
[9] Cf. e.g. I Ugi’ Isonitrile Chemistry. Academic Press. New York 1971
I101 W P. Fehlhammer. A. M a y . B. Ulgemoller, Angew. Chem. 87. 290 (1975);
Angew. Chem. Int. Ed. Engl. 14, 369 (1975)
C 13C-N=CC12
L ( C O ) & o3d-N=CC12
(3a), L
(3b), L
= CO
= PPh3
Interestingly, reaction of (2) with Fe2(C0)9 (molar ratio
1 : 1, tetrahydrofuran) proceeds by a completely different
route: at room temperature, C-C coupling takes place with
formation of metal-free (5), which is also accessible by high-
Reaction Rates of Isotopic Molecules. By L. Melander and
H . W. Saunders, Jr., Wiley, New York 1980. xiv, 391 pp.,
bound, f 16.30.
This is a completely new and extended edition of Melander’s “Isotope Effects on Reaction Rates” (Ronald, New
York 1960). A short introduction is followed in turn by the
mathematical foundations for the description and calculation
of isotope effects from molecular data, an explanation of the
measurement techniques, and the evaluation of experimental
data. The special section deals with the measurements of primary and secondary kinetic hydrogen isotope effects and
also solvent isotope effects and their interpretations. After a
description of the isotope effects of carbon and other nonmetals, the book concludes with a discussion of the techniques
for, and results from, measurements of the isotope effects in
complex reaction systems, including enzymatic reactions. A
three-part appendix provides instructions for calculations
and tables.
Particular stress is placed on detailed mathematical treatment of the isotope effect, which is used to derive reactionkinetic interpretations and mechanistic applications. The examples given have been chosen as a means of explaining the
theory. The arrangement and presentation are clear, making
it easy for the less initiated. The consistent and complete
treatment of the entire field distinguishes this book from its
competitors, which all too often concentrate on individual
aspects. Since much of the relevant work is nowadays taking
Angew. Chem Inr. Ed. Engl. 20 (1981) No. 2
place in biochemistry, we might have expected a rather
greater emphasis on this area, e. g. a description of some relevant procedures and concepts (equilibrium perturbation
method, partitioning factor). All in all, this is currently the
most authoritative book for anyone concerned with the theory, application, and interpretation of kinetic isotope effects.
F. J. Winkler [NB 534 IE]
Recent Books
Metal Ions in Biological Systems. Vol. 11. Metal Complexes
as Anticancer Agents. Edited by H . Sigel. Marcel Dekker,
New York 1980. xx, 440 pp., bound, SFr. 115.00.-ISBN
0-8247- 1004-5
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methyl, permetalated, isocyanides
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