TY - JOUR
T1 - Deacetylation of chiral ferrocenyl-containing β-diketones promoted by ethylene diamine
T2 - Spectroscopic and structural characterization of the fragmentation products
AU - Ahumada, Guillermo
AU - Soto, Juan Pablo
AU - Carrillo, David
AU - Manzur, Carolina
AU - Roisnel, Thierry
AU - Hamon, Jean René
N1 - Funding Information:
The authors thank Dr. S. Sinbandhit (CRMPO, Rennes) for helpful assistance with NMR experiments. This research has been performed as part of the Chilean-French International Associated Laboratory for “Inorganic Functional Materials” (LIAMIF-CNRS N°836). Financial support from the Fondo Nacional de Desarrollo Científico y Tecnológico [FONDECYT (Chile), grant no. 1090310 (C.M. and D.C.)], the Vicerrectoría de Investigación y Estudios Avanzados , Pontificia Universidad Católica de Valparaíso , Chile (C.M. and D.C.), the CNRS and the Université de Rennes 1 is gratefully acknowledged. G.A. Thanks the CONICYT (Chile) for support of a graduate student fellowship.
PY - 2014/11/1
Y1 - 2014/11/1
N2 - It is well known that β-diketones react with primary amines, readily forming the corresponding Schiff base derivatives. However, in the present case, the chiral ferrocenyl-containing β-diketones, 3-(1-ferrocenylethyl)- pentane-2,4-dione (1a), 1-(4-methoxyphenyl)-2-(1-ferrocenylethyl)-butane-1,3- dione (1b), and 1-ferrocenyl-2-(1-ferrocenylethyl)-butane-1,3-dione (1c) react with ethylene diamine under acidic conditions in refluxing toluene to yield, unexpectedly, their deacetylated counterparts, 3-ferrocenyl-butane-2-one (2a), 1-(4-methoxyphenyl)-3-ferrocenyl-butane-1-one (2b), and 1,3-bisferrocenyl- butane-2-one (2c), respectively. Such deacetylation reactions are accompagned by the formation of 2-methyl-2-imidazoline. A reaction mechanism involving an intramolecular Michael addition followed by a retro-Mannich rearrangement is suggested. The ketones 2a-c are fully characterized by analytical and spectroscopic methods. Additionally, compounds 2a and 2c are authenticated by single crystal X-ray diffraction analysis. The electrochemical behaviour of the bimetallic complex 2c is also investigated.
AB - It is well known that β-diketones react with primary amines, readily forming the corresponding Schiff base derivatives. However, in the present case, the chiral ferrocenyl-containing β-diketones, 3-(1-ferrocenylethyl)- pentane-2,4-dione (1a), 1-(4-methoxyphenyl)-2-(1-ferrocenylethyl)-butane-1,3- dione (1b), and 1-ferrocenyl-2-(1-ferrocenylethyl)-butane-1,3-dione (1c) react with ethylene diamine under acidic conditions in refluxing toluene to yield, unexpectedly, their deacetylated counterparts, 3-ferrocenyl-butane-2-one (2a), 1-(4-methoxyphenyl)-3-ferrocenyl-butane-1-one (2b), and 1,3-bisferrocenyl- butane-2-one (2c), respectively. Such deacetylation reactions are accompagned by the formation of 2-methyl-2-imidazoline. A reaction mechanism involving an intramolecular Michael addition followed by a retro-Mannich rearrangement is suggested. The ketones 2a-c are fully characterized by analytical and spectroscopic methods. Additionally, compounds 2a and 2c are authenticated by single crystal X-ray diffraction analysis. The electrochemical behaviour of the bimetallic complex 2c is also investigated.
KW - Chiral β-diketones
KW - Deacetylation
KW - Ethylene diamine
KW - Ferrocenyl
KW - Michael addition
KW - Retro-Mannich rearrangement
UR - http://www.scopus.com/inward/record.url?scp=84906557634&partnerID=8YFLogxK
U2 - 10.1016/j.jorganchem.2014.07.019
DO - 10.1016/j.jorganchem.2014.07.019
M3 - Article
AN - SCOPUS:84906557634
SN - 0022-328X
VL - 770
SP - 14
EP - 20
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
ER -