88229-22-5Relevant academic research and scientific papers
Stereoselective Oxidative Cyclization ofN-Allyl Benzamides to Oxaz(ol)ines
Abazid, Ayham H.,Hollwedel, Tom-Niklas,Nachtsheim, Boris J.
supporting information, p. 5076 - 5080 (2021/07/19)
This study presents an enantioselective oxidative cyclization ofN-allyl carboxamides via a chiral triazole-substituted iodoarene catalyst. The method allows the synthesis of highly enantioenriched oxazolines and oxazines, with yields of up to 94% and enantioselectivities of up to 98% ee. Quaternary stereocenters can be constructed and, besidesN-allyl amides, the corresponding thioamides and imideamides are well tolerated as substrates, giving rise to a plethora of chiral 5-memberedN-heterocycles. By applying a multitude of further functionalizations, we finally demonstrate the high value of the observed chiral heterocycles as strategic intermediates for the synthesis of other enantioenriched target structures.
A Next-Generation Air-Stable Palladium(I) Dimer Enables Olefin Migration and Selective C?C Coupling in Air
Kundu, Gourab,Rissanen, Kari,Schoenebeck, Franziska,Sperger, Theresa
supporting information, p. 21930 - 21934 (2020/10/02)
We report a new air-stable PdI dimer, [Pd(μ-I)(PCy2tBu)]2, which triggers E-selective olefin migration to enamides and styrene derivatives in the presence of multiple functional groups and with complete tolerance of air. The same dimer also triggers extremely rapid C?C coupling (alkylation and arylation) at room temperature in a modular and triply selective fashion of aromatic C?Br, C?OTf/OFs, and C?Cl bonds in poly(pseudo)halogenated arenes, displaying superior activity over previous PdI dimer generations for substrates that bear substituents ortho to C?OTf.
Preparation of Heterocycles via Visible-Light-Driven Aerobic Selenation of Olefins with Diselenides
Zhang, Qing-Bao,Yuan, Pan-Feng,Kai, Liang-Lin,Liu, Kai,Ban, Yong-Liang,Wang, Xue-Yang,Wu, Li-Zhu,Liu, Qiang
supporting information, p. 885 - 889 (2019/02/14)
The aerobic dehydrogenative cyclization of alkenes with easily accessible diselenides facilitated by visible light is reported. Notably, the features of this transition-metal-free protocol are pronounced efficiency and practicality, good functional group
Silver-Promoted Synthesis of 5-[(Pentafluorosulfanyl)methyl]-2-oxazolines
Gilbert, Audrey,Bertrand, Xavier,Paquin, Jean-Fran?ois
supporting information, p. 7257 - 7260 (2018/11/23)
The synthesis of 5-[(pentafluorosulfanyl)methyl]-2-oxazolines is reported. The use of a silver promoter allows the intramolecular cyclization of N-[2-chloro-3-(pentafluorosulfanyl)propyl]amide to occur without elimination of the chlorine atom, a reaction
Group 13 metal carbochalcogenoato complexes: Synthesis, X-ray structure analysis, and reactions
Nakata, Norio,Kato, Shinzi,Niyomura, Osamu,Ebihara, Masahiro
, (2018/11/23)
A series of alkali metal tetrakis(carbochalcogenoato)-gallates and -indates M[M′(EOCR)4](solv.) (M?=?alkali metal; M′?=?Ga, In; E?=?S, Se) and tris(carbodithioato)aluminum, -gallates and -indates M′ (SSCR)3 (M′?=?Al, Ga, In) were prepared by the reactions of alkali metal carbochalcogenate with metal trihalogenides (M′X3; M′?=?Al, Ga, In; X?=?Cl, Br) and by those of piperidinium carbodithioates or carbodithioic and carboselenoic acids with M′X3, respectively. An X-ray molecular structure analysis revealed that they have an acetone molecule as a crystal solvent. The reactions of the potassium complexes K[M′ (EOCR)4](H2O) (E?=?S, Se) with methanol and primary and secondary amines gave the corresponding methyl ester and amides in good yields, while the reactions with iodomethane and iodine gave S- and Se-methyl chalcogenoesters RCOEMe (E?=?S, Se) in good yields. Similar reactions of the tris(carbodithioato)gallates and -indates led to the corresponding O-methyl thioesters, thioamides, and S-methyl dithioesters in moderate to good yields. Oxidation of the tetrakis- and tris-derivatives with iodine afforded the corresponding diacyl dichalcogenides (RCOE)2 (E?=?S, Se) and di(carbothioyl) disulfides in quantitative yields. These reactions appeared to occur on the carbonyl or selenium atom of the tetrakis compounds and on the sulfide sulfur or thiocarbonyl carbon atom of the tris-compounds, respectively. A possible mechanism for these I2-oxidation reactions is discussed.
XtalFluor-E mediated proto-functionalization of: N -vinyl amides: Access to N -acetyl N, O -acetals
Yi,Gholami,Morrow,Borhan
supporting information, p. 9570 - 9574 (2017/11/30)
XtalFluor-E has been extensively used in a broad range of reactions in the past few years. Here we report its use with protic nucleophiles in a catalytic manner for the in situ generation of protons that lead to the proto-functionalization of activated ol
Copper-Catalyzed Divergent Trifluoromethylation/Cyclization of Unactivated Alkenes
Zheng, Jing,Deng, Ziyang,Zhang, Yan,Cui, Sunliang
supporting information, p. 746 - 751 (2016/03/09)
Most of the precedent copper-catalyzed trifluoromethylation reactions of unactivated alkenes concern terminal alkenes, and these processes are terminated in elimination, or nucleophilic addition, or semipinacol rearrangement, or C-H bond functionalization steps. In this study, we develop a trifluoromethylation method for both unactivated terminal and internal alkenes to enable divergent late-stage radical cyclization and achieve high molecular complexity. These cyclizations are well consistent with Baldwin's rule. Furthermore, a kinetic isotope effect (KIE) study and control reactions were conducted, and a plausible mechanism is proposed.
Transamidation of primary amides with amines using hydroxylamine hydrochloride as an inorganic catalyst
Allen, C. Liana,Atkinson, Benjamin N.,Williams, Jonathan M. J.
supporting information; experimental part, p. 1383 - 1386 (2012/04/18)
Metal-free catalysis: A method for the transamidation of primary amides with primary or secondary amines provides access to secondary and tertiary amides, by utilizing catalytic quantities of hydroxylamine hydrochloride to activate the chemically robust primary amide group (see scheme). A mechanism of primary amide activation through a hydrogen-bonding complex is proposed. Copyright
Amides as precursors of imidoyl radicals in cyclisation reactions
Bowman, W. Russell,Fletcher, Anthony J.,Pedersen, Jan M.,Lovell, Peter J.,Elsegood, Mark R.J.,Hernández López, Elena,McKee, Vickie,Potts, Graeme B.S.
, p. 191 - 203 (2007/10/03)
Amides have been successfully used as precursors of imidoyl radicals for radical cyclisation. The amides have been converted to imidoyl selanides via reaction with phosgene to yield imidoyl chlorides followed by reaction with potassium phenylselanide. Imidoyl selanides were reacted with tributyltin hydride (Bu3SnH) as the radical mediator with triethylborane or AIBN as initiators to yield imidoyl radicals for cyclisation reactions. Imidoyl radicals have been cyclised onto alkenes to yield 2,3-substituted-indoles and -quinolines and also onto pyrroles and indoles to give bi- and tricyclic heteroarenes.
The triphenyl phosphite-chlorine reagent in the synthesis of pyrroles from N-allylamides
Spaggiari, Alberto,Vaccari, Daniele,Davoli, Paolo,Prati, Fabio
, p. 995 - 998 (2007/10/03)
A novel application of (PhO)3P-Cl2 chemistry to the synthesis of 2-substituted and 2,3-disubstituted pyrroles from N-allyl-amides is illustrated. A mild procedure is used to generate the imino chloride intermediates, which are subseq
