Half Sandwich Electron Deficient N, N′, N′′‐Triarylguanidinatoruthenium(II) Complexes: Syntheses, Reactivity Studies, and Structural Aspects. Issue 31 (12th August 2019)

• Record Type: Journal Article
• Authors: Kumar, Robin; Ujjval, Rishabh; Thirupathi, Natesan
• Is Part Of: European journal of inorganic chemistry. Issue 31(2019)
• Page Start: 3619
• Page End: 3628
• Publication Date: 2019-08-12
• Subjects: Half sandwich complexes -- Ruthenium -- Electron deficient guanidinates -- Linkage isomers -- Cycloaddition; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201900616
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract : Three symmetrical N, N′, N′′ ‐triarylguanidinatoruthenium(II) complexes, [(η 6 ‐ p ‐cymene)RuCl{κ 2 ( N, N′ )((ArN)2 C‐N(H)Ar)}] (Ar = 2‐(CF3 )C6 H4 (1 ), 4‐(CF3 )C6 H4 (2 ) and 3, 5‐(CF3 )2 C6 H3 (3 )) were isolated in good yields. The reaction of 3 with NaOAc, NaN3 and KSCN afforded [(η 6 ‐ p ‐cymene)RuX{κ 2 ( N, N′ )((ArN)2 C‐N(H)Ar)}] (X = OAc (4 ), N3 (5 ) and an admixture of SCN (6 ) and NCS (7 )) respectively in very good yields. On the other hand, metathesis reaction of 3 with AgSbF6 in the presence of MeCN afforded [(η 6 ‐ p ‐cymene)Ru(MeCN){κ 2 ( N, N′ )((ArN)2 C‐N(H)Ar)}][SbF6 ] (8 ) in good yield. Complex 5 upon treatment with diethylacetylenedicarboxylate and bis(diphenylphosphanyl)acetylene separately afforded guanidinate(1–) complex, [(η 6 ‐ p ‐cymene)Ru(N3 C2 (C(O)OEt)2 ){κ 2 ( N, N′ )((ArN)2 C‐N(H)Ar)}] (9 ) and guanidinate(2–) complex, [(η 6 ‐ p ‐cymene)Ru{κ 2 ( N, N′ )((ArN)2 C=NAr)}(κ 1 P ‐Ph2 PC≡CPPh2 )] (10 ) in good yields. The formation 9 vs. 10 is ascribed to the subtle difference in the electron richness of alkynes. The new complexes were characterized by analytical, IR and NMR spectroscopy and single‐crystal X‐ray diffraction. Complex 3 catalyses [3+2] cycloaddition reaction involving phenylacetylene and 4‐tolyl azide to afford an admixture of 1, 4‐ and 1, 5‐disubstituted 1, 2, 3‐triazoles, 23 and 24 in 99 % conversion. Abstract : [3+2] Cycloaddition reaction of 5 with electron deficient diethylacetylenedicarboxylate afforded guanidinate(1–) complex 9, while the reaction with electron rich bis(diphenylphosphanyl)acetylene afforded guanidinate(2–) complex 10 in good yields. The difference in reactivity was ascribed to the difference in the electron richness of the reacting alkynes.