201053-62-5Relevant academic research and scientific papers
Kinetic addition of nucleophiles to η3-propargyl rhenium complexes occurs at the central carbon to produce rhenacyclobutenes
Casey, Charles P.,Nash, John R.,Yi, Chae S.,Selmeczy, Anthony D.,Chung, Steven,Powell, Douglas R.,Hayashi, Randy K.
, p. 722 - 733 (1998)
Kinetic addition of nucleophites occurs at the center carbon of η3-propargyl rhenium complexes to produce rhenacyclobutenes. Reaction of P(CH3)3 with C5Me5(CO)2Re[η3-CH2C≡CC(CH3)3]+BF4- (3a) gave the metallacyclobutene C5Me5(CO)2ReCH2C(PMe3)=CC(CH3)3+BF4- (4a), which was characterized by X-ray crystallography. Malonate and acetylide nucleophiles reacted with C5Me5(CO)2Re[η3-CH2C≡CCH3]+PF6- (3b) to give metallacyclobutene complexes. Pyridine added to the central propargyl carbon of 3b at low temperature to produce the metastable metallacyclobutene C5Me5(CO)2ReCH2C(NC5H5)=CCH3+PF6- (14b) which rearranged to the η2-allene complex C5Me5(CO)2Re[η2-H2C=C=C(NC5H5)CH3]+PF6- (15K) at room temperature. 4-(Dimethylamino)pyridine (DMAP) added to the central carbon of the tert-butyl-substituted η3-propargyl complex 3a below -38°C to give the rhenacyclobutene complex C5Me5(CO)2ReCH2C-C(NC5H4NMe2)=CC(CH3)3+BF4- (22a) which rearranged to the η2-alkyne complex C5Me5(CO)2Re[η2-(CH3)3-CC≡CCH2NC5H4NMe2]+BF4- (23) at room temperature. Reaction of water with C5Me5(CO)2Re[η3-CH2C≡CH]+BF4-(3c) gave the hydroxyallyl complex C5Me5(CO)2Re[η3-CH2C(OH)CH2]+BF4- (29) by a process proposed to involve nucleophilic addition of water to the central propargyl carbon of 3c followed by protonation of the metallacyclobutene intermediate.
Quantitative determination of the regioselectivity of nucleophilic addition to η3-propargyl rhenium complexes and direct observation of an equilibrium between η3-propargyl rhenium complexes and rhenacyclobutenes
Casey, Charles P.,Boiler, Timothy M.,Samec, Joseph S. M.,Reinert-Nash, John R.
, p. 123 - 131 (2009/05/30)
PMe3 adds selectively to the central carbon of the η3-propargyl complex [C5Me5(CO) 2Re(η3-CH2C=CCMe3)][BF 4] (1-t-Bu) to form the metallacyclobutene [C
