1,2σ3λ3-Oxaphosphetanes and Their P-Chalcogenides—A Combined Experimental and Theoretical Study

Abstract

Although 1,2σ5λ5-oxaphosphetanes have been known for a long time, the “low-coordinate” 1,2σ3λ3-oxaphosphetanes have only been known since their first synthesis in 2018 via decomplexation. Apart from ligation of this P-heterocycle to gold(I)chloride and the oxidation using ortho-chloranil, nothing on their chemistry has been reported so far. Herein, we describe the synthesis of new 1,2σ3λ3-oxaphosphetane complexes (3a–e) and free derivatives (4a–e), as well as reactions of 4a with chalcogens and/or chalcogen transfer reagents, which yielded the P-chalcogenides (14–16a; Ch = O, S, Se). We also report on the theoretical results of the reaction pathways of C-phenyl-substituted 1,2 σ3λ3-oxaphosphetanes and ring strain energies of 1,2σ4λ5-oxaphosphetane P-chalcogenides.

Arbuzov meets 1,2-oxaphosphetanes: transient 1,2-oxaphosphetan-2-iums as an entry point to beta-halo phosphane oxides and P-containing oligomers

“…Our established protocol enabled us to isolate 1,2-oxaphosphetane 6, but 7 could only be observed as a mixture in solution (Scheme 2). 27,29 Complexes 4 and 5 as well as the ''free'' 1,2-oxaphosphetane 6 were structurally confirmed via single crystal X-ray diffraction (SC-XRD) studies. Interestingly, the structural features of 4 and 6 (Fig.…”

“…27 Subsequently, we reported on an elusive 1,2σ 4 λ 5 -oxaphos-phetane P-oxide ( VI ) and also on a stable P-sulfide and a P-selenide, formerly unknown. 29…”

“…27 Subsequently, we reported on an elusive 1,2s 4 l 5 -oxaphos-phetane P-oxide (VI) and also on a stable P-sulfide and a P-selenide, formerly unknown. 29 Fig. 1 Oxetane (I), phosphetanes (s 3 l 3 IIa, s 5 l 5 IIb), 1,3-oxaphosphetanes (s 3 l 3 IIIa, s 5 l 5 IIIb), 1,2-oxaphosphetanes (s 3 l 3 IVa, s 5 l 5 IVb), 1,2s 3 l 3 -oxaphosphetane metal complexes (V), 1,2s 4 l 5 -oxaphosphetanes (VI) and 1,2 s 4l 4 -oxaphos-phetan-2-ium (VII).…”