Synthese und Reaktion der ersten 1,2‐Oxaphosphetankomplexe

Kyri, Andreas Wolfgang; Nesterov, V. I.; Schnakenburg, Gregor; Streubel, Rainer

doi:10.1002/ange.201404877

Cited by 5 publications

(3 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The former are the first examples of such complexes and are in stark contrast to the known P V -1,2-oxaphosphetanes; ring-opening reactions relying on the cleavage of the P−O bond were reported. 4,69 The 1,2-thiaphosphetanes display an unusually low HOMO− LUMO gap and hence represent possible redox-active catalysts. 68,70 We have also recognized that the variety of reactions of Li/ Cl phosphinidenoid complexes is much broader than the phosphinidene-like reactions described beforehand, i.e., they open a new avenue to rare, highly reactive (open-shell) phosphanyl complexes.…”

Section: ■ Typical Intermolecular Reactionsmentioning

confidence: 99%

M/X Phosphinidenoid Metal Complex Chemistry

et al. 2021

Self Cite

View full text Add to dashboard Cite

Conspectus Like singlet carbenes and silylenes, transient electrophilic terminal phosphinidene complexes enabled highly selective synthetic transformations, but the required multistep synthetic protocols precluded widespread use of these P1 building blocks. By contrast, nucleophilic M/Cl phosphinidenoid complexes can be easily accessed in one step from [M(CO) n (RPCl2)] complexes. This advantage and the mild reaction conditions opened broad synthetic applicability that enabled access to a variety of novel compounds. The chemistry will be described in this Account, including bonding and mechanistic considerations derived from high-level density functional theory calculations. In 2007, we gained the first strong evidence for the formation of these thermally labile complexes using two different synthetic approaches: P–H deprotonation and Cl/Li exchange; the latter has become the preferred method. Intense studies revealed that steric demand of the P substituents in combination with metal complexation, a donor solvent, and/or the presence of a crown ether are necessary prerequisites for the formation and especially the usability of these intermediates as novel P1 building blocks. Solution-phase NMR spectroscopy and solid-state X-ray diffraction studies revealed the bonding situation, i.e., a solvent-separated ion pair structure, and typical 31P NMR signatures of the anions. To date, we have established the following reactivity patterns for Li/Cl phosphinidenoid complexes: self-condensations (I), electrophilic and nucleophilic reactions (II), 1,1-additions (III), [2 + 1] cycloadditions (IV), ring expansions (V), and redox reactions (VI). For example, self-condensations can yield dinuclear acyclic or polycyclic diphosphane or diphosphene complexes. Their use as nucleophiles and electrophiles can be employed to access functional phosphane ligands with mixed substitution patterns. 1,1-Addition reactions were a puzzling discovery because the resulting products resembled classical P–C π-bond structures but the bonding was more of a donor-to-phosphorus adduct with significant differences in bonding parameters. Into the same category and also surprising fall formal E–H insertion reactions leading to 1,1′-bifunctional phosphane complexes. To date, the most important synthetic impact was achieved in the chemistry of strained P-heterocyclic ligands such as oxaphosphiranes and azaphosphiridines, obtained via [2 + 1] cycloadditions of the title compounds with carbonyls and imines, respectively. Ring expansions have been shown to yield 1,2-oxaphosphetanes and 1,2-thiaphosphetanes, and because of the pool of industrially important epoxides, this provides straightforward and affordable access to these novel P-heterocyclic ligands, which also promise to be of interest in catalytic applications. Recent developments describe redox transformations of Li/Cl phosphinidenoid complexes into new reactive intermediates such as complexes with open-shell P-functional phosphanyl ligands via oxidative single electron transfer reactions or into te...

show abstract

Section: ■ Typical Intermolecular Reactionsmentioning

confidence: 99%

M/X Phosphinidenoid Metal Complex Chemistry

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Remarkable in the molecular structure of 10 (Figure ) is a disorder showing two different orientations of the C substituent at C1 and two different folding angles of 34.4 and 21.1°, thus also revealing the flexibility of the ring: i.e., the ease of adopting different folding angles. This was discussed previously for the first 1,2-oxaphosphetane complex structures assuming to represent a reason for the unexpectedly large number of isomers …”

Section: Resultsmentioning

confidence: 99%

“…Somehow similarly, 1,2-oxaphosphetane complexes VIa , b were formed regioselectively, but instead of two four different isomers were observed in the case of the P -CH(SiMe 3 ) 2 derivative due to atropisomerism at the exocyclic P–C bond . In the case of styrene oxide a different regioisomer was obtained, thus disfavoring the least hindered ring carbon atom and favoring a reaction at the benzylic position; the regiochemistry of VIc was again unequivocally established by single-crystal X-ray diffraction studies . As questions concerning regio- and stereoselectivity remained, we decided to examine this aspect.…”

Section: Introductionmentioning

confidence: 99%

C-Trifluoromethyl-Substituted 1,2-Oxaphosphetane Complexes: Synthetic and Structural Study

2016

Self Cite

View full text Add to dashboard Cite

Recently, the first synthetic route to 1,2-oxaphosphetane complexes was described, but the formation of too many isomers was a clear drawback and hampered further studies. Herein, we present significant advances with this problem using trifluoromethyl epoxide (4), 1,1′-bis(trifluoromethyl) epoxide (5), and differently substituted Li/Cl phosphinidenoid complexes 1–3 (R = CH(SiMe3)2, CPh3, C5Me5), thus giving 1,2-oxaphosphetane complexes 6–10 with high selectivity.

show abstract

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

Graham

Macdonald

Boyle

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

The phosphorus-sulfur heterocycles 1,2-thiaphosphetenes and phosphirene sulfides have been prepared, and represent the first structurally characterized derivatives for either class of compound. These strained P-S ring systems are formed by the reaction of a phosphinidene sulfide and alkyne. Using an internal alkyne, only the 3-membered P , phosphirene sulfide was produced, whereas a terminal alkyne yielded a mixture of phosphirene sulfide and 1,2-thiaphosphetene (P ). Detailed computational analysis revealed that for numerous derivatives of alkynes, the corresponding 4-membered rings are always more stable than the 3-membered isomers. The electronic nature of "free" phosphinidene sulfides (R-P=S) is discussed based on computational results.

show abstract

Synthese und Reaktion der ersten 1,2‐Oxaphosphetankomplexe

Cited by 5 publications

References 40 publications

M/X Phosphinidenoid Metal Complex Chemistry

M/X Phosphinidenoid Metal Complex Chemistry

C-Trifluoromethyl-Substituted 1,2-Oxaphosphetane Complexes: Synthetic and Structural Study

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

Contact Info

Product

Resources

About