Synthesis and Reaction of the First 1,2‐Oxaphosphetane Complexes

Abstract

While P(V) 1,2-oxaphosphetanes are well known from the Wittig reaction, their P(III) analogues are still unexplored. Herein, the synthesis and reactions of the first 1,2-oxaphosphetane complexes are presented, which were achieved by reaction of the phosphinidenoid complex [Li(12-crown-4)(solv)][(OC)5W{(Me3Si)2HCPCl}] with different epoxides. The title compounds appeared to be stable in toluene up to 100 °C, before unselective decomposition started. Acid-induced ring expansion with benzonitrile resulted in selective formation of the first complex bearing a 1,3,4-oxazaphosphacyclohex-2-ene ligand.

Access to 1,1′‐Bifunctional Phosphane Iron(0) Complexes via P–N Bond‐Forming Reactions and Selective P‐Functionalizations

“…Taking this background into account, we recently envisaged a chance to broaden access to complexes V and, perhaps, also to VI using the versatile chemistry of Li/Cl phosphinidenoid complexes, in general, and the formal insertion reaction into N–H bonds in particular. In doing so, we were able to build up a versatile collection of secondary aminophosphanes while being coordinated to a transition metal fragment .…”

Addressing the Nature of Phosphinidene Sulfides via the Synthesis of P−S Heterocycles

“…In this particular case, structural characterization of the first 1,2-oxaphosphetane [1] and NMR spectroscopic data [2] favoured the formation of the strained 4-membered PÀOh eterophosphete. [3][4][5][6][7][8][9] Although chemistry of the 1,2-oxaphosphetanes, either containing transition-metal stabilized P III (A) [10][11][12][13] or pentavalent phosphorus (B) [14][15][16][17] have been studied, the heavierc halcogen derivativesa re considerably underdeveloped in comparison. The most common examples of heterophosphetes containing heavierc halcogens are 1,2-thiaphosphetanes, which containa saturated 4-membered PSC 2 ring and ap entavalentp hosphorus atom (C & D).…”

Synthesis, Properties and Stereochemistry of 2-Halo-1,2λ⁵-oxaphosphetanes

“…Evidently, this conversion represents an example of a thermodynamically stable oxaphosphetanes, in which pseudorotation is faster than alkene formation (Scheme 4). Most of the previously reported stable oxaphosphetane structures contain fluorine-bearing or bicyclic phosphole-type ligands either at the phosphorus position or at the 4 position in the oxaphosphetane ring 10,11 [15][16][17][18][19][20]. Recently, Streubel and coworkers have prepared the first 1,2-oxaphosphetane complexes 12 formally similar to traditional oxaphosphetanes, using lowtemperature ring expansion of epoxides with a Li/Cl phosphinidenoid complex [18] (Scheme 5).…”

“…The reaction of ylides 14 with aldehydes is regioselective. For example, the oxaphosphetanes obtained by reaction of silylated P-chloroylide 5 with terephthalic aldehyde depending on a ratio of initial reactants led to the formation of 1,4-bis-vinylphosphonobenzene or phosphonovinylbenzaldehyde, that represent interest as reactants for organic synthesis (See Table 6, entries 10,11) [13,[18][19][20]. The 2-fluoro-1,2λ 5 -oxaphosphetanes enter readily into a number of interesting organophosphorus compounds proceeding without Р-С bond cleavage [26].…”