33224-90-7Relevant academic research and scientific papers
Steroid Derived Mesoionic Gold and Silver Mono- and Polymetallic Carbenes
Frutos, María,De La Torre, María C.,Sierra, Miguel A.
, p. 11174 - 11185 (2015)
A two-step synthesis of gold mesoionic carbene complexes containing estrone moieties has been developed. The method uses the methylation of the triazole nucleus, followed by the treatment of the triazolium salt with Ag2O and transmetalation wit
Aldol-Tishchenko Reaction of α-Oxy Ketones: Diastereoselective Synthesis of 1,2,3-Triol Derivatives
Sedano, Carlos,Virumbrales, Cintia,Suárez-Pantiga, Samuel,Sanz, Roberto
supporting information, p. 3725 - 3734 (2021/07/02)
α-Oxy ketones, easily accessible by conventional routes, can be selectively deprotonated generating an enolate intermediate, which upon treatment with paraformaldehyde undergoes an aldol-Tishchenko reaction, leading to relevant 1,2,3-triol fragments in a totally diastereoselective manner. The excellent stereocontrol in the generation of a quaternary stereocenter is attributed to stereoelectronic effects in the Evans intermediate. This methodology allows overcoming some limitations of our previously reported strategy, based on the reaction of α-lithiobenzyl ethers with esters and paraformaldehyde, broadening the scope of the obtained polyols. Synthetic applications of this process include the preparation of a new dilignol model and some functionalized oxetanes.
Chiral N-heterocyclic carbene ligands for asymmetric catalytic oxindole synthesis
Jia, Yi-Xia,Hillgren, J. Mikael,Watson, Emma L.,Marsden, Stephen P.,Kuendig, E. Peter
supporting information; scheme or table, p. 4040 - 4042 (2009/03/11)
The Pd-catalysed asymmetric intramolecular α-arylation of amide enolates containing heteroatom substituents gives chiral 3-alkoxy or 3-aminooxindoles in high yield and with enantioselectivities up to 97% ee when a new chiral N-heterocyclic carbene ligand is used. The Royal Society of Chemistry.
Hypervalent iodine oxidation of trimethylsilyl ketene acetals: A convenient route to α-methoxylation of esters and lactones
Moriarty, Robert M.,Rani, Neena,Condeiu, Cristian,Duncan, Michael P.,Prakash, Om
, p. 3273 - 3277 (2007/10/03)
Hypervalent iodine oxidation of trimethylsilyl ketene acetals of esters and lactones using iodosobenzene in methanol affords the corresponding α- methoxylated carbonyl compounds in good yields.
Synthesis and anticonvulsant activity of some substituted lactams and amides
Brouillette,Grunewald
, p. 202 - 206 (2007/10/02)
Thirteen derivatives of 3-phenyl-2-piperidinone were synthesized and evaluated for anticonvulsant activity. The most active compounds from this group included two simple lactams, 3-hydroxy-1-methyl-3-phenyl-2-piperidinone and 3-methoxy-3-phenyl-2-piperidi
Carbenes in a Rigid Matrix. Substituent Effects on the Temperature Dependence of α-Carbonylcarbene Reactions
Tomioka, Hideo,Okuno, Hiroshi,Izawa, Yasuji
, p. 1636 - 1641 (2007/10/02)
The temperature dependence of methoxycarbonyl- (1a and b) and benzoyl-carbenes (2a and b) reactions in alcohols has been examined in order to elucidate the scope and limitation of low temperature photolysis as a tool for detecting triplet carbenes.The results reveal that the method cannot be applied to all carbenes but gives important information on the reactivity and/or multiplicity of ground-state carbenes.Low-temperature photolysis of PhCN2CO2Me in an ethanol matrix, for example, resulted in a dramatic increase in C-H insertion products, probably derived from the triplet (1a) via an abstraction-recombination mechanism, at the expense of the singlet product, i.e. the O-H insertion compound, which was shown to be the main product of photolysis at ambient temperature.In marked contrast, (1b) generated in a propan-2-ol matrix at -196 deg C did not result in a major increase in the C-H insertion product.Similar and more contrasting substituent effects on the temperature dependence were observed in the benzoylcarbene system (2).Thus, the Wolff rearrangement of (2a) was almost completely supressed in a rigid matrix at -196 deg C, whereas that of (2b) was not appreciably supressed even at -196 deg C.These differences were explained by considering the effects of the substituent on the ground-state multiplicity of carbene and/or on the relation of the activation energy differences of the singlet and triplet reactions with energy differences between two states.
