On Route to C⁴/C⁵ P‐Bifunctional 1,3‐Thiazole‐Based Carbenes

Abstract

A facile synthetic protocol enables the synthesis of the 4‐phosphanyl‐5‐thiophosphanoyl thiazole‐2‐thione 1 through the selective lithiation of the 5‐thiophosphanoyl thiazole‐2‐thione VIb followed by reaction with chlorodiphenylphosphane. The reaction of 1 with elemental sulfur leads to the PV/PV homochalcogenide thiazole‐2‐thione 2. The heterochalcogenide thiazole‐2‐thione 4 was obtained through the reaction of PIII/PV‐substituted thiazole‐2‐thione VIb with H2O2–urea. All compounds were characterized by 31P, 1H, and 13C NMR spectroscopy, IR spectroscopy, elemental analysis, mass spectrometry, and single‐crystal X‐ray diffraction studies.

From P‐Functional Thiazol‐2‐thione Derivatives to Phosphaalkenes

“…Recently, we have published a facile synthetic protocol to achieve the C 4 and/or C 4 / C 5 ‐phosphanylated thiazol‐2‐thiones in good to high yields , . Using the same backbone functionalization approach, the 5‐bis(diethylamino)phosphanyl‐thiazol‐2‐thione ( 2 ) was accessed via lithiation of thiazol‐2‐thione ( 1 ) with tert ‐butyllithium followed by addition of the electrophilic bis(diethylamino)chlorophosphane (Scheme ).…”

“…For example, we reported the synthesis and reactivity of a mono‐substituted C 5 ‐phosphanoyl‐thiazol‐2‐thione, its phosphanoyl‐thiazolium salt, and its rhodium(I) complex . In addition, the synthesis and characterization of disubstituted derivatives such as mixed valence P(III/V) thiazol‐2‐thiones as well as homo and hetero‐bis‐P‐chalcogenides P(V/V) was achieved . Besides being potential precursors for bisphosphanoyl‐substituted thiazol‐2‐ylidenes and tricyclic 1,4‐diphosphinines, we envisaged that such compounds may also provide access to other novel fascinating low‐coordinate phosphorus compounds such as phosphaalkenes and their polymers.…”

Synthesis and Oxidation Reactions of Thiazol‐2‐thione‐fused 1,4‐Dihydro‐1,4‐diphosphinines

“…[10] It should be noted that in most of the examples discussed beforehand ( Figure 1) [1-3,6-9,10b] the P-centers possessed always alkyl or aryl groups, except for VI and VII. [9,10b] More recently, we started to develop the chemistry of Cphosphanylated thiazol-2-thiones including reactivity studies, comprising oxidation of the P-center [11] and a second phosphanylation, [12] but also the oxidative desulfurization giving access to a P-functional thiazolium salt and its deprotonation in the presence of metal source to afford the NHC-metal complex. [11] Very recently, the chemistry was further extended by the advent of the first thiazol-2-thione-derived 1,4-diphophinine which was used to access a stable monoanion, reported in a short communication.…”

“…Hydrogen atoms have been omitted for clarity. Selected bond lengths (Å) and angles (°) of 4: C2-S2 1.672(3), C6-S4 1.667(4), C1-P(1) 1.818(4), C5-P(2) 1.824(4), N3-P(2) 1.682(3), N1-C2-S1 108.2(2), N2-C6-S3 108.8(2), S1-C1-P 121.8(2), S3-C5-P 128.4(2), C1-PÀ C5 96.77(16) and 5a: C3-S2 1.6659(12), C7-S4 1.6706(12), C1-P1 1.8344(12), C5-P2 1.8326(12), N4-P2 1.6729(11), N1-C3-S1 108.94(8), N2-C7-S3 108.75(8), S1-C2-P2 115.83(7), S3-C6-P1 116.40(6), C1-PÀ C6 96.60(5).…”