Linked Life Data

18937411

Source:http://linkedlifedata.com/resource/pubmed/id/18937411

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2008-11-14
pubmed:abstractText
Various divalent lanthanide complexes with the formula LnL2(sol)x (L = N(TMS)2, sol = THF, x = 3, Ln = Sm (I), Eu (II), Yb (III); L = MeC5H4, sol = THF, x = 2, Ln = Sm (IV); L = ArO(Ar = [2,6-((t)Bu)2-4-MeC6H2]), sol = THF, x = 2, Ln = Sm (V)), especially complexes I- III, serve as excellent catalyst precursors for catalytic addition of various primary and secondary amines to carbodiimides, efficiently providing the corresponding guanidine derivatives with a wide range of substrates under solvent-free condition. The reaction shows good functional groups tolerance. Complexes I- III are also excellent precatalysts for addition of terminal alkynes to carbodiimides yielding a series of propiolamidines. The active sequence of Yb < Eu < Sm for metal and MeC5H4 < ArO < N(TMS)2 for ligand around the metal was observed for both reactions. The first step in both reactions was supposed to include the formation of a bimetallic bisamidinate samarium species originating from the reduction-coupling reaction of carbodiimide promoted by lanthanide(II) complex. The active species is proposed to be a lanthanide guanidinate and a lanthanide amidinate.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1520-6904
pubmed:author
pubmed:issnType
Electronic
pubmed:day
21
pubmed:volume
73
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8966-72
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Divalent lanthanide complexes: highly active precatalysts for the addition of N-H and C-H bonds to carbodiimides.
pubmed:affiliation
Key Laboratory of Organic Synthesis of Jiangsu Province, Department of Chemistry and Chemical Engineering, Suzhou University, Dushu Lake Campus, Suzhou University, Suzhou 215123, People's Republic of China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't