141330-12-3Relevant articles and documents
Novel Synthesis of Heterocycles Using Zirconium-Catalyzed Diene Cyclization
Uesaka, Noriaki,Mori, Miwako,Okamura, Kimio,Date, Tadamasa
, p. 4542 - 4547 (1994)
The catalytic cyclization of the diene 1 by Cp2ZrCl2 in the presence of BuMgBr gives the hexahydroindole derivative 2.The stereochemistry of the zirconacycle 10 is different from that of the zirconacycle 7, which is obtained from 1 under stoichiometric conditions.Carbon-carbon bond formation results from treatment of the intermediary magnesium complex 8 with various electrophiles, such that various heterocycles were synthesized.
A lutidine-promoted photoredox catalytic atom-transfer radical cyclization reaction for the synthesis of 4-bromo-3,3-dialkyl-octahydro-indol-2-ones
Zhao, Quan-Sheng,Xu, Guo-Qiang,Xu, Ji-Tao,Wang, Zhu-Yin,Xu, Peng-Fei
supporting information, p. 2206 - 2209 (2020/02/26)
Reported herein is a visible-light-catalyzed photoredox atom-transfer radical cyclization (ATRC) halo-alkylation of 1,6-dienes with α-halo-ketones as the ATRC reagent. This process exhibits high atom economy, high step economy, and high redox economy, which can directly construct a 4-bromo-3,3-dialkyl-octahydro-indol-2-one core under mild conditions in one pot, and lutidine is found to be the key promoter for this ATRC process.
A One-Pot Iodo-Cyclization/Transition Metal-Catalyzed Cross-Coupling Sequence: Synthesis of Substituted Oxazolidin-2-ones from N-Boc-allylamines
Chaumont-Olive, Pauline,Cossy, Janine
supporting information, (2020/05/14)
A one-pot iodo-cyclization/transition metal-catalyzed cross-coupling sequence is reported to access various C5-functionalized oxazolidin-2-ones from unsaturated N-Boc-allylamines. Depending on the Grignard reagents used for the cross-coupling, e.g., aryl- or cyclopropylmagnesium bromide, a cobalt or copper catalyst has to be used to obtain the functionalized oxazolidin-2-ones in good yields.
C-N Bond Formation from Allylic Alcohols via Cooperative Nickel and Titanium Catalysis
Nazari, S. Hadi,Tiempos-Flores, Norma,Forson, Kelton G.,Bourdeau, Jefferson E.,Michaelis, David J.
, p. 10646 - 10654 (2018/09/06)
Amination of allylic alcohols is facilitated via cooperative catalysis. Catalytic Ti(O-i-Pr)4 is shown to dramatically increase the rate of nickel-catalyzed allylic amination, and mechanistic experiments confirm activation of the allylic alcohol by titanium. Aminations of primary and secondary allylic alcohols are demonstrated with a variety of amine nucleophiles. Diene-containing substrates also cyclize onto the nickel allyl intermediate prior to amination, generating carbocyclic amine products. This tandem process is only achieved under our cooperative catalytic system.
Copper-Catalyzed Intramolecular Oxidative Amination of Unactivated Internal Alkenes
Xiong, Peng,Xu, Fan,Qian, Xiang-Yang,Yohannes, Yared,Song, Jinshuai,Lu, Xin,Xu, Hai-Chao
supporting information, p. 4379 - 4383 (2016/03/22)
A copper-catalyzed oxidative amination of unactivated internal alkenes has been developed. The Wacker-type oxidative alkene amination reaction is traditionally catalyzed by a palladium through a mechanism involving aminopalladation and β-hydride elimination. Replacing the precious and scarce palladium with a cheap and abundant copper for this transformation has been challenging because of the difficulty associated with the aminocupration of internal alkenes. The combination of a simple copper salt, without additional ligand, as the catalyst and Dess-Martin periodinane as the oxidant, promotes efficiently the oxidative amination of allylic carbamates and ureas bearing di- and trisubstituted alkenes leading to oxazolidinones and imidazolidinones. Preliminary mechanistic studies suggested a hybrid radical-organometallic mechanism involving an amidyl radical cyclization to form the key C-N bond.
Switching and Conformational Fixation of Amides Through Proximate Positive Charges
Bartuschat, Amelie L.,Wicht, Karina,Heinrich, Markus R.
supporting information, p. 10294 - 10298 (2015/09/01)
Tertiary amides, which usually occur as cis/trans mixtures, can be effectively shifted to the cis conformation by placing a positive charge in close proximity to the amide carbonyl. This effect was used to prepare cis-configured prolyl amides and to facilitate a strongly rotamer-dependent radical cyclization. Taking charge of conformation: Tertiary amides, which usually occur as cis/trans mixtures, can be effectively shifted to the cis conformation by placing a positive charge in close proximity to the amide carbonyl. This effect was used to prepare cis-configured prolyl amides and to facilitate a strongly rotamer-dependent radical cyclization.
HEPATITIS B ANTIVIRAL AGENTS
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Page/Page column 217, (2013/07/05)
The present invention includes a method of inhibiting, suppressing or preventing HBV infection in an individual in need thereof, comprising administering to the individual a therapeutically effective amount of at least one compound of the invention.
Semipinacol rearrangement of cis-fused β-lactam diols into keto-bridged bicyclic lactams
Grainger, Richard S.,Betou, Marie,Male, Louise,Pitak, Mateusz B.,Coles, Simon J.
supporting information; experimental part, p. 2234 - 2237 (2012/06/30)
The 6-azabicyclo[3.2.1]octane ring system, prevalent in a range of biologically active molecules, is prepared through a novel semipinacol rearrangement utilizing a cyclic phosphorane or sulfite intermediate. The rearrangement proceeds with exclusive N-acyl group migration of a β-lactam ring and results in carbonyl functionality at the 7- and bridging 8-position of the bicycle. Precursor ring-fused β-lactam diols are prepared through a sequence of 4-exo trig carbamoyl radical cyclization, regioselective dithiocarbamate group elimination, and dihydroxylation.
Ammonium-directed olefinic epoxidation: Kinetic and mechanistic insights
Brennan, Meabh B.,Claridge, Timothy D.W.,Compton, Richard G.,Davies, Stephen G.,Fletcher, Ai M.,Henstridge, Martin C.,Hewings, David S.,Kurosawa, Wataru,Lee, James A.,Roberts, Paul M.,Schoonen, Anne K.,Thomson, James E.
, p. 7241 - 7261 (2012/11/07)
The ammonium-directed olefinic epoxidations of a range of differentially N-substituted cyclic allylic and homoallylic amines (derived from cyclopentene, cyclohexene, and cycloheptene) have been investigated, and the reaction kinetics have been analyzed. The results of these studies suggest that both the ring size and the identity of the substituents on nitrogen are important in determining both the overall rate and the stereochemical outcome of the epoxidation reaction. In general, secondary amines or tertiary amines with nonsterically demanding substituents on nitrogen are superior to tertiary amines with sterically demanding substituents on nitrogen in their ability to promote the oxidation reaction. Furthermore, in all cases examined, the ability of the (in situ formed) ammonium substituent to direct the stereochemical course of the epoxidation reaction is either comparable or superior to that of the analogous hydroxyl substituent. Much slower rates of ring-opening of the intermediate epoxides are observed in cyclopentene-derived and cycloheptene-derived allylic amines as compared with their cyclohexene-derived allylic and homoallylic amine counterparts, allowing for isolation of these intermediates in both of the former cases.
Diastereodivergent hydroxyfluorination of cyclic and acyclic allylic amines: Synthesis of 4-deoxy-4-fluorophytosphingosines
Cresswell, Alexander J.,Davies, Stephen G.,Lee, James A.,Morris, Melloney J.,Roberts, Paul M.,Thomson, James E.
, p. 7262 - 7281 (2012/10/30)
A diastereodivergent hydroxyfluorination protocol enabling the direct conversion of some conformationally biased allylic amines to the corresponding diastereoisomeric amino fluorohydrins has been developed. Sequential treatment of a conformationally biased allylic amine with 2 equiv of HBF 4·OEt2 followed by m-CPBA promotes epoxidation of the olefin on the face proximal to the amino group under hydrogen-bonded direction from the in situ formed ammonium ion. Regioselective and stereospecific epoxide ring-opening by transfer of fluoride from a BF 4- ion (an SN2-type process at the carbon atom distal to the ammonium moiety) then occurs in situ to give the corresponding amino fluorohydrin. Alternatively, an analogous reaction using 20 equiv of HBF4·OEt2 results in preferential epoxidation of the opposite face of the olefin, which is followed by regioselective and stereospecific epoxide ring-opening by transfer of fluoride from a BF 4- ion (an SN2-type process at the carbon atom distal to the ammonium moiety). The synthetic utility of this methodology is demonstrated via its application to a synthesis of 4-deoxy-4-fluoro-l-xylo- phytosphingosine and 4-deoxy-4-fluoro-l-lyxo-phytosphingosine, each in five steps from Garner's aldehyde.
