- Asymmetric synthesis of the fully functionalized six-membered ring of trigoxyphin A
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An asymmetric synthesis strategy of the fully functionalized six-membered ring of trigoxyphin A, a daphnane-type diterpenoid, has been accomplished concisely from a d-tartrate derivative. Key elements of this synthesis involve the tandem ozonization/intramolecular HWE reaction to construct the α,β-unsaturated cyclohexenone skeleton, the radical cyclization to introduce the C8 chirality and sequential Kumada cross-coupling/hydroboration-oxidation to introduce the C11 chirality. The target substructure could be synthetically achieved on a multi-gram scale.
- Feng, Jing,Yu, Tianzi,Zhang, Zhijiang,Li, Jinpeng,Fu, Shaomin,Chen, Juan,Liu, Bo
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- Preparation and Application of Amino Phosphine Ligands Bearing Spiro[indane-1,2′-pyrrolidine] Backbone
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P,Nsp3-bidentate chiral ligands bearing spiro[indane-1,2′-pyrrolidine] backbone were prepared in gram scale for the first time. Pd complexes of these air-stable amino phosphine ligands could catalyze asymmetric allylic substitutions of malonate-, alcohol-, and amine-type nucleophiles in up to 97percent ee and 99percent yield. A crystal structure of [Pd(II)(η3-1,3-diphenylallyl)(ligand)]PF6 indicated possible transition states of the catalytic reactions. These ligands are characteristic of a very rigid backbone, which is simple but highly effective. They rival C2-symmetric bisphosphine, P,Nsp2-bidentate, and P,Nsp3-bidentate ligands in tested allylic substitutions. ?
- Feng, Lifei,Jiao, Peng,Li, Hongjie,Li, Shasha,Zhang, Jinxia
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p. 9460 - 9473
(2019/08/26)
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- N-triflyl-propiolamides: Preparation and transamidation reactions
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N-Trifluoromethylsulfonyl-propiolamides have been prepared by two methods: a) N-triflation of secondary acetylenic carboxanilides, prepared in two steps from terminal alkynes, with triflic anhydride (Tf2O) and b) from terminal alkynes and an aryl or alkyl isocyanate followed by Tf2O in a consecutive one-pot reaction. The title compounds are bench-stable and insensitive to water and alcohols but amenable to transamidation reactions with a wide range of amine nucleophiles. Conversely, they are excellent reagents for the propynoylation of ammonia, primary and secondary amines, anilines, and hydrazines.
- Fiore, Vito A.,Maas, Gerhard
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p. 3586 - 3595
(2019/05/27)
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- Sulfoxide ligand metal catalyzed oxidation of olefins
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The enantioselective synthesis of isochroman motifs has been accomplished via Pd(II)-catalyzed allylic C—H oxidation from terminal olefin precursors. Critical to the success of this goal was the development and utilization of a novel chiral aryl sulfoxide-oxazoline (ArSOX) ligand. The allylic C—H oxidation reaction proceeds with the broadest scope and highest levels asymmetric induction reported to date (avg. 92% ee, 13 examples ≥90% ee). Additionally, C(sp3)-N fragment coupling reaction between abundant terminal olefins and N-triflyl protected aliphatic and aromatic amines via Pd(II)/sulfoxide (SOX) catalyzed intermolecular allylic C—H amination is disclosed. A range of 52 allylic amines are furnished in good yields (avg. 76%) and excellent regio- and stereoselectivity (avg. >20:1 linear:branched, >20:1 E:Z). For the first time, a variety of singly activated aromatic and aliphatic nitrogen nucleophiles, including ones with stereochemical elements, can be used in fragment coupling stiochiometries for intermolecular C—H amination reactions.
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Page/Page column 118-119
(2019/05/09)
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- Selective cleavage of the N-propargyl group from sulfonamides and amides under ruthenium catalysis
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The selective cleavage of the N-propargyl group from sulfonamides and amides under ruthenium catalysis is described. The reaction tolerates a broad range of functional groups, and the desired products were obtained in 10–95% yield.
- Wang, Jingjing,Li, Feng,Pei, Wenlong,Yang, Mixue,Wu, Yidan,Ma, Danyang,Zhang, Furong,Wang, Jianhui
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supporting information
p. 1902 - 1905
(2018/04/19)
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- SUBSTITUTED PYRROLO[2,3-B]-PYRIDINES AND-PYRAZINES
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Compounds of Formula I, as shown below and defined herein:(I) pharmaceutically acceptable salts, synthesis, intermediates, formulations, and methods of disease treatment therewith, including cancers mediated at least in part by Ron and/or Met.
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Page/Page column 47
(2010/07/10)
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- DERIVATIVES OF UREAS OF PIPERIDINE OR PYRROLIDINE, THEIR PREPARATION AND THEIR THERAPEUTICAL USE
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The present invention is related to a compound of formula (I): wherein i, j, n, o, p, q, r, R1a, R1b, R1c, R1d, R2a, R2b, R2c, R2d, R3a, R3b and R4 are as defined herein, or an addition salt with an acid thereof, or a hydrate or solvate thereof, its preparation, pharmaceutical composition, and uses for treating a disease in which the enzyme 11β-HSD1 is involved.
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Page/Page column 33-34
(2009/07/18)
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- Triflamides and triflates of six-membered heterocyclic amines
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Reactions of secondary cyclic amines (piperidine, morpholine, thiomorpholine, 1λ6,4-thiazinane-1,1-dione) with trifluoromethanesulfonic anhydride or with N-phenyltriflimide both in the presence and in the absence of a base (Et3N) result in formation of corresponding triflamides and triflates of the initial amines. The triflates and triflamides can be distinguished by their 19F and 15N NMR spectra and the presence in the IR spectra of salts of absorption bands in the region 3270-3000 cm-1 lacking in the spectra of triflamides.
- Shainyan,Tolstikov,Zhinkin
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p. 1180 - 1182
(2007/10/03)
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- SYNTHESIS OF PYRIMIDINYL TRIFLATES AND PALLADIUM-CATALYZED COUPLING WITH ORGANOTIN AND ORGANOZINC REAGENTS
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Pyrimidinyl triflates have been synthesized from pyrimidinones using triflic anhydride in the presence of triethylamine.The triflates, in the pyrimidine electrophilic positions, are versatile intermediates for substitution reactions.Carbon substituents ar
- Sandosham, Jessie,Undheim, Kjell
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p. 501 - 514
(2007/10/02)
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- Electrophilic fluorination of aromatic compounds
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A process for the electrophilic ring fluorination of aromatic compounds which comprises reacting a fluorinating agent from the group consisting of CF3 OF and CF2 (OF)2 with an aromatic compound of the formula STR1 where X is selected from the group consisting of STR2 and STR3 and Y is selected from the group consisting of --H, --CF3, --CN, --NO2, --Cl, and CH3.
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- Trifluoromethanesulfonanilides, and their production and use
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A herbicidal composition which comprises as an active ingredient a trifluoromethanesulfonanilide of the formula: STR1 wherein R1 and R2 are, the same or different, each a hydrogen atom, a halogen atom or a C1 -C4 alkyl group, R3 and R4 are, the same or different, each a hydrogen atom, a C1 -C4 alkyl group, a C3 -C6 cycloalkyl group, a C3 -C4 alkenyl group, a C3 -C5 alkynyl group, a C1 -C4 alkoxy group, a C6 -C7 aralkyl group, a C1 -C4 alkoxy(C1 -C4)alkyl group or a C2 -C5 acyl group or they may be combined together with the nitrogen atom to form a morpholino group and X is a C2 -C5 acyl group, provided that R3 and R4 are not simultaneously a hydrogen atom or a C2 -C5 acyl group.
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- REACTION OF PYRIDINE N-OXIDES WITH TRIFLIC ANHYDRIDE: FORMATION OF N-SULFONYLOXY AND DIPYRIDINIUM ETHER SALTS
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Pyridine and picoline-N-oxides react with (CF3SO2)2O to give N-sulfonyloxy and dipyridinium ether triflate salts.
- Chen, Zhen-Chu,Stang, Peter J.
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p. 3923 - 3926
(2007/10/02)
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- Process for preparing amides by reaction in presence of molecular sieve
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There is provided a process for preparing amides which comprises reacting an amine, or an amide, and an acid halide, or anhydride, in suitable molecular proportions, in an inert organic diluent, in the presence of an effective amount of a molecular sieve, until the reaction is completed, separating the molecular sieve, and recovering the amide from the organic mother liquor.
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