Chemistry of Phosphorus Ylides: Part 44 Reaction of 1-Trimethylsilyl-1H-Imidazole with Phosphorus Reagents. A Convenient Synthesis of Phosphorus Silyl Imidazoles

Abstract

Trimethylsilylimidazoles have received much attention because of their synthetic and application challenges. 1,2 Moreover, the trimethylsilyl group is characterised by chemical inertness and a large molecular volume, which makes it useful in a number of applications. [3][4][5] Trimethylsilylimidazoles are used as silyl protecting and derivatisation reagents, 6,7 reducing agents, 8 in cross-coupling chemistry 9 and to stabilise α-carbanions and β-carbocations. 9 Previously we studied the reactions of the active phosphacumulenes, phosphallenes, stabilised phosphonium ylides, Lawesson and Japanese reagents to prepare new heterocyclic and homocyclic compounds containing phosphorus moieties of industrial and biological interest. [10][11][12][13][14][15][16][17][18][19] Results and discussionWe now report the reaction of 1-trimethylsilyl-1H-imidazole (1) with (N-phenyliminovinylidene)triphenylphosphorane (2a), (2-oxovinylidene)triphenylphosphorane (2b), hexaphenylcarbodiphosphorane (5), Lawesson's reagent (8a) and Japanese reagent 9a (Schemes 1-4). The phosphacumulene ylides (2a and 2b) can each be described by the resonance structures 2A and 2B (Scheme 1). Accordingly, treatment of 1 with 1 equiv. of 2a in dry toluene led to the formation of imidazolesilylphosphoranylidene aniline 3a. When the reaction was performed in hot THF and the product was chromatographed on silica gel, the new compound imidazolephosphoranylidene aniline 4a was isolated. Adduct 3a was formed by nucleophilic attack of 2a on 1 and fast exchange

Design, synthesis, and biological evaluation of new heterocycles bearing both silicon and phosphorus as potent MMP‐2 inhibitors

“…It was reported that the reactions of active phosphacumulene ylides with isocyanate and isothiocyanate form different heterocyclic compounds containing phosphorus and sulfur moieties [43] with different biological activities. [44][45][46][47][48][49][50] In our ongoing studies, we investigated the reactions of active phosphacumulenes and phosphallene ylides with silicon isothiocyanate to produce different heterocycles containing phosphorus and silicon moieties of biological interest. Thus, the reaction of isocyanatotrimethylsilane (1) with (N-phenyliminovinylidene)triphenylphosphorane (2) upon stirring in dry THF yielded a mixture of N 2 -phenyl-N 4 -(trimethylsilyl)-3-(triphenyl-λ 5 -phosphaneylidene)oxetane-2,4-diimine (4) [51] and N 4 -phenyl-N 2 -N 6 -bis(trimethylsilyl)-5-(triphenyl-λ 5phosphaneylidene)-1,3-dioxane-2,4,6-triimine (5).…”

Chemistry of Phosphorus Ylides: Part 46—Efficient Synthesis and Biological Evaluation of New Phosphorus, Sulfur, and Selenium Pyrazole Derivatives

“…In our continuing studies, we have described the development of new biomolecules of therapeutic interest from the reaction of active and stabilized phosphonium ylides with bioactive natural and unnatural products with potential applications in medicinal chemistry [14][15][16][17][18][19][20][21]. By reacting 1,5-dimethyl-3-oxo-2-phenyl-2,3dihydro-1H-pyrazole-4-carbaldehyde (1) with (Nphenyliminovinylidene)-triphenylphosphorane (2a) in tetrahydrofuran (THF), compound 1,7a-dimethyl-2phenyl-6-(phenylimino)-7-(triphenylphosphoranylidene)-1, 6,7,7a-tetrahydropyrano [4,3-c]pyrazol-3(2H)-one (3a) was obtained.…”

The synthesis and antineoplastic activities of thiaziridine, sulfidometylphosphonium, and dithiaphosphitane‐sulfide against the Ehrlich ascites carcinoma

“…The current study was conducted to synthesis new series of phosphorus compounds derived from isothiocyanate and isocyanate substrates that follow the line F I G U R E 1 Chemical structures of some anticancer drugs of our previous researches to create new antitumor heterocyclic and homocyclic compounds bearing phosphorus moieties [26][27][28][29][30][31][32][33]. Likewise, the anticancer potential activities of these compounds are assessed in comparison with 5-Fluorouracil against EAC in mice.…”