16149-89-6Relevant academic research and scientific papers
Hydroxylamine catalyzed Nazarov cyclizations of divinyl ketones Dedicated to Professor Hilton Weiss on his 80th birthday
Hamilton, Joseph Z.,Kadunce, Nathaniel T.,McDonald, Michael D.,Rios, Laura,Matlin, Albert R.
, p. 6622 - 6624 (2015)
The first examples of iminium catalyzed Nazarov cyclizations of divinyl ketones are presented. Experiments describing hydroxylamine catalysis of the cyclization of eight α-alkoxy divinyl ketones (60-79% yield) and one unactivated divinyl ketone (38% yield) are reported. Phenyl substitution at the β-position of the divinyl ketone inhibits cyclization, whereas β-alkyl substituted α-alkoxy divinyl ketones readily cyclize.
Synthesis and structure of ansa-metallocene complexes (M=ZrCl2, TiCl2, YCl, and LuCl) containing the bis(2-methyl-4,5,6,7-tetrahydroinden-yl)dimethylsilane ligand
Halterman, Ronald L.,Schumann, Herbert,Dübner, Frank
, p. 12 - 19 (2000)
The three step synthesis of 2-methyl-4,5,6,7-tetrahydro-1H-indene from cyclohexyl methacrylate is described [(a) PPA cyclization; (b) LiAlH4 reduction; (c) HCl dehydration]. This annelated trisubstituted cyclopentadiene was bridged selectively to form ethylene- or dimethylsilyl-bridged bis(2-methyl-4,5,6,7-tetrahydro-1H-inden-1-yl) ligands. Metal complexes (M=ZrCl2, TiCl2, YCl, and LuCl) of the bis(2-methyl-4,5,6,7-tetrahydroinden-1-yl)dimethylsilane ligand were formed as meso/dl stereoisomeric mixtures in ratios from 1:1 to 2:1 dl:meso.
Synthesis of spiro[4.5]decane and bicyclo[4.3.0]nonane ring systems by self-cyclization of (Z)- and (E)-2-(trimethylsilylmethyl)pentadienal derivative
Kuroda, Chiaki,Honda, Shigenobu,Nagura, Yuki,Koshio, Hiroyuki,Shibue, Taku,Takeshita, Tokio
, p. 319 - 331 (2007/10/03)
The two title carbon frameworks were synthesized utilizing a new type of iron-induced cyclization reaction of 2-(trimethylsilylmethyl)pentadienal. 2-Methylspiro[4.5]dec-2-en-1-one was obtained from (Z)- and (E)-4- cyclohexylidene-2-(trimethylsilylmethyl)but-2-enal. It was found that the (Z)-substrate isomerized to (E)-intermediate followed by cyclization to afford the initial product, 2-methylenespiro[4.5]dec-3-en-1-ol, which was isomerized to the above product. The cyclization of 4-(4-alkyl)cyclohexylidene-2- (trimethylsilylmethyl)but-2-enal proceeded stereoselectively. While, (E)-3-(cyclohex-1-en-1-yl)-2-(trimethylsilylmethyl)prop-2-en-1-al cyclized immediately affording 8-methylenebicyclo[4.3.0]non-9-en-7-ol. The corresponding (Z)-isomer gave several cyclization products as a complex mixture.
