Trifluoromethyl phosphaalkenes of the type F₃CPC(OR)NR₂: Synthesis, spectroscopic investigations, and ligand properties [1]

Abstract

ABSTRACT

On the d6-Transition Metal Complex Formation of Electron-Rich Methylenephosphanes, a Quantum Chemical Investigation

“…After coordination, the phosphorus atom becomes slightly pyramidal, in agreement with the experiments. [31,41] The sum of valence angles for C-amino substitution are as follows: Cr 348.9°, Mo 353.9°, W 350.9°. This matter can be touched on in the limiting structures shown in Scheme 5.…”

The chemistry of fluorine containing phosphaalkenes, arsaalkenes and selenocarbonyls

“…They do not react with HX agents or 1,3-dienes, but function as P-4e-donors if coordinated to BH 3 [41] or transition metal complex fragments [30,42]. Compounds of type C take an intermediate position between those of types B and D. Thus, the PC double bond adds secondary amines or alcohols with formation of the phosphaalkenes F 3 CP¼C(OR)NR 2 and F 3 CP¼C(OR)OR 0 [30,31], respectively, proving F 3 C(H)P-C(F)OR(NR 2 ) and F 3 C(H)P-CF(OR)OR 0 as intermediates. Besides, derivatives of type C in contrast to those of type D slowly dimerize to give the corresponding diphosphetanes and react with electron-poor 1,3-dienes yielding the expected Diels-Alder adducts.…”

“…The presently known representatives include the C-alkoxy derivatives F 3 CP¼C(F)OR [28], F 3 CP¼C(OR)NR 2 [30], F 3 CP¼C(OR)OR 0 (R, R 0 ¼ Me, Et) [31] and the C-amino derivatives HP¼C(F)NR 2 [32], F 3 CP¼C(F)NR 2 (R ¼ Me, Et, nPr) [29], R 0 P¼C(F)NEt 2 (R 0 ¼ Me 2 P, Me 2 As, (F 3 C) 2 P, (F 3 C) 2 As, Me 2 N(F 3 C)P [33]; Me 3 Si, Me 3 Ge, (F 3 C) 3 Ge, Me 3 Sn [34]; CO(OMe) [31]). …”

Reaktive E=C(p–p)π-Systeme, XXXVI [1] Darstellung, Reaktivität und Ligandeneigenschaften des Trifluormethyl-1,3-diphosphans tBu(H)PCF2P(H)CF3 / Reactive E=C(p—p)π Systems, XXXVI [1]. Synthesis, Reactivity and Ligand Properties of the Trifluoromethyl-1,3-diphosphane tBu(H)PCF2P(H)CF3

“…Perfluor-Effekt [3] und weist infolge der spezi ellen Substituentenkom bination bei äußerst gerin ger Polarität einen ausgeprägten olefinischen C ha rakter auf. Diese Eigenschaften ergeben sich aus seiner Elektronenstruktur [4] und werden aus fol genden experimentellen Befunden deutlich: a) 1 reagiert mit 1,3-Dienen bzw. Diazomethanderivaten glatt zu [4 + 2]-bzw.…”