64233-13-2Relevant articles and documents
Platinum-catalyzed intramolecular hydrohydrazination: Evidence for alkene insertion into a Pt-n bond
Hoover, Jessica M.,Dipasquale, Antonio,Mayer, James M.,Michael, Forrest E.
scheme or table, p. 5043 - 5053 (2010/06/13)
Dicationic (bpy)Pt(II) complexes were found to catalyze the intramolecular hydrohydrazination of alkenes. Reaction optimization revealed Pt(bpy)Cl 2 (10 mol %) and AgOTf (20 mol %) in DMF-d7 to be an effective catalyst system for the conversion of substituted hydrazides to five- and six-membered N-amino lactams (N-amino = N-acetamido at 120 A°C, N-phthalimido at 80 A°C, -OTf = trifluoromethanesulfonate). Of the four possible regioisomeric products, only the product of 5-exo cyclization at the proximal nitrogen is formed, without reaction at the distal nitrogen or 6-endo cyclization. The resting states were found to be a 2:1 Pt-amidate complex (25, for N-acetamido) of the deprotonated hydrazide and a Pt-alkyl complex of the cyclized pyrrolidinone (20 for N-phthalimido). Both complexes are catalytically competent. Catalysis using 25 as the precatalyst shows no rate dependence on added acid (HOTf) or base (2,6-lutidine). The available mechanistic data are all consistent with a mechanism involving N-H activation of the hydrazide, followed by insertion of the alkene into the Pt-N bond, and finally protonation of the resulting cyclized alkyl complex by hydrazide to release the hydrohydrazination product and regenerate the active Pt-amidate catalyst.
APPLICATIONS OF THE THERMAL ENE REACTION OF ALDEHYDE t-BUTYL- AND PHENYL- HYDRAZONES
Baldwin, Jack E.,Adlington, Robert M.,Jain, Ashok U.,Kolhe, Jayant N.,Perry, Matthew W. D.
, p. 4247 - 4252 (2007/10/02)
The Thermal Ene reaction of aldehyde t-butyl- and phenyl- hydrazones with enophiles gave C-trapped azo-adducts which can be diverted into synthetically useful γ-keto-esters, γ-keto-nitriles, γ-alkyl-2-pyrrolidones, and γ-amino-esters.
Michael Additions of Hydrazones for Carbon-Carbon Bond Formation
Baldwin, Jack E.,Adlington, Robert M.,Bottaro, Jeffrey C.,Jain, Ashok U.,Kolhe, Jayant N.,et al.
, p. 1095 - 1096 (2007/10/02)
The lithium salts of t-butyl- and trityl-hydrazones react with methyl crotonate to form C-trapped azo-esters and similar products were observed from a thermal ene-reaction of aldehyde t-butylhydrazones with methyl acrylate or acrylonitrile, and aldehyde phenylhydrazones with methyl acrylate; these products can be diverted into synthetically useful γ-keto-esters, γ-keto-nitriles, saturated esters, γ-alkyl-2-pyrrrolidones, and γ-amino-esters.
