Synthesis and structure of para‐toluene sulfonamide lanthanide complexes and their application in the polymerization of ε‐caprolactone. (19th June 2017)

• Record Type: Journal Article
• Authors: Wang, Li‐Jun; Peng, Ling; Cen, Bo; Wang, Yu‐Long; Tao, Xian; Shen, Ying‐Zhong
• Is Part Of: Applied organometallic chemistry. Volume 31:Number 12(2017:Dec.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-06-19
• Subjects: homoleptic lanthanide complexes -- para‐toluene sulfonamides -- polymerization; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.3828
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : A series of para‐toluene sulfonamide ligands [TsNHPr‐i(HL 1 ), TsNHBu‐t(HL 2 ), TsNHPh(HL 3 ), TsNHPhMe‐p(HL 4 ), TsNHPhOMe‐p(HL 5 )] were synthesized by amidation using para‐toluene sulfonyl chloride reacting with different primary amines. A series of homoleptic lanthanide complexes (Ln L3, 1–10) (Ln = La, L = L1 (1 ), Ln = Gd, L = L2 (2 ), Ln = La, L = L2 (3 ), Ln = Gd, L = L2 (4 ), Ln = La, L = L3 (5 ), Ln = Gd, L = L3 (6 ), Ln = La, L = L4 (7 ), Ln = Gd, L = L4 (8 ), Ln = La, L = L5 (9 ), Ln = Gd, L = L5 (10 )) were prepared by amine elimination reactions of the ligands with Ln[N(SiMe3 )2 ]3 (Ln = La, Gd). Complexes1, 3, 5, 7 and9 were all characterized by NMR spectra, and the structures of complex3 was determined by single‐crystal X‐ray diffraction. Complex3 crystallizes a binuclear cluster, consisting of two La 3+ and six (TsNBu‐t) − anions. Three (TsNBu‐t) − anions are chelating to each La 3+ as bidentate model with O and N forming three‐membered chelate rings; one of three anions is bridging to another La 3+ via oxygen. All complexes were characterized using elemental analysis and infrared spectra. The catalytic properties of complexes1–10 for the ring‐opening polymerization of ε‐caprolactone were studied and the results showed that all complexes are efficient initiators for this ring‐opening polymerization reaction. Abstract : The preparation of ten lanthanide complexes bearing para‐toluene sulfonamide ligands were obtained by the reaction of Ln[N(TMS)2 ]3 (Ln = La, Gd) with para‐toluene sulfonamides is described. The crystal structure of Complex3 was determined and discussed. The catalytic properties of complexes1 ‐10 for the ring‐opening polymerization of ε‐caprolactone were studied and the results showed that all complexes are efficient initiators for this ring‐opening polymerization.