Zhang, Wen-Xiong; Nishiura, Masayoshi; Hou, Zhaomin published the artcile< Catalytic addition of amine N-H bonds to carbodiimides by half-sandwich rare-earth metal complexes: efficient synthesis of substituted guanidines through amine protonolysis of rare-earth metal guanidinates>, Reference of 115955-90-3, the main research area is half sandwich rare earth catalyst guanidine synthesis carbodiimide amine.
Reaction of [Ln(CH2SiMe3)3(thf)2] (Ln = Y, Yb, and Lu) with one equivalent of Me2Si(C5Me4H)NHR’ (R’ = Ph, 2,4,6-Me3C6H2, tBu) affords straightforwardly the corresponding half-sandwich rare-earth metal alkyl complexes [{Me2Si(C5Me4)(NR’)}Ln(CH2SiMe3)(thf)n] (1: Ln = Y, R’ = Ph, n = 2; 2: Ln = Y, R’ = C6H2Me3-2,4,6, n = 1; 3: Ln = Y, R’ = tBu, n = 1; 4: Ln = Yb, R’ = Ph, n = 2; 5: Ln = Lu, R’ = Ph, n = 2) in high yields. These complexes, especially the yttrium complexes 1-3, serve as excellent catalyst precursors for the catalytic addition of various primary and secondary amines to carbodiimides, efficiently yielding a series of guanidine derivatives with a wide range of substituents on the nitrogen atoms. Functional groups such as CN, CCH, and aromatic C-X (X: F, Cl, Br, I) bonds can survive the catalytic reaction conditions. A primary amino group can be distinguished from a secondary one by the catalyst system, and therefore, the reaction of 1,2,3,4-tetrahydro-5-aminoisoquinoline with iPrN=C=NiPr can be achieved stepwise first at the primary amino group to selectively give the monoguanidine, and then at the cyclic secondary amino unit to give the biguanidine. Some key reaction intermediates or true catalyst species, such as the amido complexes [{Me2Si(C5Me4)(NPh)}Y(NEt2)(thf)2] and [{Me2Si(C5Me4)(NPh)}Y(NHC6H4Br-4)(thf)2], and the guanidinate complexes [{Me2Si(C5Me4)(NPh)}Y{iPrNC(NEt2)(NiPr)}(thf)] and [{Me2Si(C5Me4)(NPh)}Y{iPrN}C(NC6H4Br-4)(NHiPr)(thf)] have been isolated and structurally characterized. Reactivity studies on these complexes suggest that the present catalytic formation of a guanidine compound proceeds mechanistically through nucleophilic addition of an amido species, formed by acid-base reaction between a rare-earth metal alkyl bond and an amine N-H bond, to a carbodiimide, followed by amine protonolysis of the resultant guanidinate species.
Chemistry – A European Journal published new progress about Amines, triamines Role: PEP (Physical, Engineering or Chemical Process), RCT (Reactant), PROC (Process), RACT (Reactant or Reagent). 115955-90-3 belongs to class tetrahydroisoquinoline, and the molecular formula is C9H12N2, Reference of 115955-90-3.
Referemce:
Tetrahydroisoquinoline – Wikipedia,
1,2,3,4-Tetrahydroisoquinoline | C9H11N – PubChem