Structure and mechanism of formation of the metallooxacyclobutane complex bis(triphenylarsine)tetracyanooxiraneplatinum, the product of the reaction between tetracyanooxirane and tetrakis(triphenylarsine)platinum

Abstract

Metallooxacyclobutane complexes, Pt[C2(CN)40]L2 (L = P(C6H5)3, P(p-CH3C6H4)3, As(C6H5)3), were prepared from the reaction between tetracyanooxirane (2,2,3,3-tetracyanooxacyclopropane, C2(CN)40) and PtL4. The crystal and molecular structure of the complex where L = As(C6H5)3 has been determined from three-dimensional X-ray diffraction data. The crystal has symmetry consistent with the space group Ph/c [CV] with four molecules of the complex in a unit cell of dimensions a = 9.933 (2) A, b = 20.477 (3) A, c = 18.634 (3) A, and ß - 95.42 (1)°. The structure was refined by least-squares techniques to a conventional R index of 0.039 based on 4819 reflections above background collected using a four-circle diffractometer. The structure determination shows that Pt[As(C6H5)3]2 has inserted into the carbon-oxygen bond of the oxirane. Such a metallooxacyclobutane ring has recently been suggested as an intermediate in the catalytic formation of ethylene carbonate from Ni°c omplexes, ethylene oxide, and C02. Comparisons are made between the structural parameters of the present complex, the closely related metallocyclobutane complex Pt[C2(CN)4CH2][P(C6Hs)3]2, and the small rings tetracyanooxirane and 1,1,2,2-tetracyanocyclopropane. Spectroscopic data and chemical behavior of the metallooxacyclobutane complexes are reported.

C‐terminal Tensin‐like (CTEN) is an oncogene which alters cell motility possibly through repression of E‐cadherin in colorectal cancer

“…intermediate, which can dimerize to hexacyanobutadiene ( 9 ), or form tricyanomethanide, [C(CN) 3 ] − ( 10 ), or 5 , again by unknown mechanisms (Scheme ). Compound 6 has also been reported to form from the reaction of TCNEO ( 8 ) and, for example, [Pt 0 (AsPh 3 ) 4 ], which additionally can form 11 with the cis ‐C(CN) 2 C(CN) 2 ‐ linkage 3 ($\tilde \nu $ CN =2220 cm −1 ; $\tilde \nu $ CO =1072 cm −1 ) 21…”

Tetracyanoethylene (TCNE): The Characteristic Geometries and Vibrational Absorptions of Its Numerous Structures

“…Compound 6 has also been reported to form from the reaction of TCNEO (8) and, for example, [Pt 0 -A C H T U N G T R E N N U N G (AsPh 3 ) 4 ], which additionally can form 11 with the cis-C(CN) 2 C(CN) 2 -linkage 3 (ñ CN = 2220 cm À1 ; ñ CO = 1072 cm À1 ). [21] The reaction of Na 2 À1 , respectively). [22] Compound 12 is a chelating ligand and several [M (12) 2 ] complexes have been characterized, while acidification forms H12 (ñ CN = 2233 cm À1 ).…”

“…À has also been reported to form a s bond (20) as well as cis-1,1' bonding (21), and other isomers can be envisioned. Compound 22 has been reported for [Rh 2 - [26a] but because of disorder the structure is too poorly refined to get reliable metric parameters.…”

Theoretical study on the mechanism of nickel(0)-mediated coupling between carbon dioxide and epoxyethane

“…Unfortunately, these intermediates have not been isolated to date, though a few transition-metal-carbon dioxide complexes [31][32][33] similar to 7 and some oxametallacyclobutanes [34][35][36] similar to 2 have been observed. One may wonder whether NiL 2 complexes first react with epoxides to give intermediate 2 or ligate CO 2 to form intermediate 7.…”