479423-40-0Relevant academic research and scientific papers
Enantioselective Construction of Sulfur-Containing Tetrasubstituted Stereocenters via Asymmetric Functionalizations of α-Sulfanyl Cyclic Ketones
Ye, Xueqian,Pan, Yongkai,Chen, Yunrong,Yang, Xiaoyu
supporting information, p. 3374 - 3379 (2020/07/16)
Asymmetric functionalizations of α-sulfanyl cyclic ketones were realized via chiral phosphoric acid catalyzed enantioselective addition reactions with aldimines, azodicarboxylates and allenamides. A series of chiral organosulfur compounds possessing sulfur-containing tetrasubstituted stereocenters were accessed via these methods, with excellent regioselectivities and high stereoselectivities. (Figure presented.).
γ-Selective Vinylogous Aza-Morita-Baylis-Hillman Reaction with N -Carbamoylimines
Gondo, Naruhiro,Tanigaki, Yusuke,Ueda, Yoshihiro,Kawabata, Takeo
, p. 398 - 402 (2020/02/27)
Vinylogous aza-Morita-Baylis-Hillman (aza-MBH) reactions of a vinylcyclopentenone with N -Boc imines provide the corresponding γ-adducts in high regioselectivity (10 examples). While the corresponding reactions with N -Ts imines give the α-adducts and γ-a
Silver-Catalyzed Enantioselective Mannich Reaction of Diazoacetate Esters with N-Boc Aldimines
Robertson, Gerard P.,Farley, Alistair J. M.,Dixon, Darren J.
, p. 2785 - 2792 (2020/02/04)
The highly enantioselective Mannich reaction of diazoacetate esters with N-Boc aldimines catalyzed by silver(I) triflate in the presence of (R)-DM-SEGPHOS is reported. The reaction is broad in scope with respect to the (hetero)aromatic aldehyde-derived al
Two Distinct Ag(I)- And Au(I)-Catalyzed Olefinations between α-Diazo Esters and N-Boc-Derived Imines
Kardile, Rahul Dadabhau,Liu, Rai-Shung
supporting information, p. 6452 - 6456 (2019/09/06)
Metal-catalyzed reactions between α-diazo esters and imines were well-known to yield aziridine derivatives exclusively. This work reports two new olefination reactions between N-Boc-derived (Boc = tert-Butyloxycarbonyl) imines and α-diazo esters with Ag(I) and Au(I) catalysts, respectively. Our mechanistic studies reveal that these new olefinations involve an initial attack of diazo esters on metal/imine complexes to form Mannich-addition intermediates, which subsequently afford α-aryl-β-aminoacrylates via a Roskamp reaction, or to form β-aryl-β-aminoacrylates via the formation of silver carbenes.
Direct enantioselective Mannich reactions of α-azido cyclic ketones: Asymmetric construction of chiral azides possessing an α-quaternary stereocenter
Ye, Xueqian,Pan, Yongkai,Yang, Xiaoyu
, p. 98 - 101 (2019/12/25)
Direct enantioselective Mannich reactions of α-azido cyclic ketones with aldimines are realized through chiral phosphoric acid catalysis, which generate chiral azides possessing an α-quanternary stereocenter with complete regioselectivities and high diast
Synthesis of highly substituted 2-spiropiperidines
Griggs, Samuel D.,Thompson, Nathan,Tape, Daniel T.,Fabre, Marie,Clarke, Paul A.
, p. 6663 - 6674 (2018/09/29)
2-Spiropiperidines are a highly desirable, yet under represented structure in drug discovery. 2-Spiropiperidines were synthesised in either a two-pot or one-pot reaction. In the two-pot reaction, the addition of a Weiler dianion to N-Boc imines, followed by deprotection and in situ condensation with a cyclic ketone generated functionalised 2-spiropiperidines in good to excellent yields. In the one-pot reaction, the addition of Chan's diene to N-Boc imines under Maitland-Japp conditions, followed by the addition of sodium bicarbonate and a cyclic ketone formed functionalised 2-spiropiperidines in moderate to good yields.
Direct Catalytic Asymmetric Mannich-Type Reaction en Route to α-Hydroxy-β-amino Acid Derivatives
Sun, Bo,Pluta, Roman,Kumagai, Naoya,Shibasaki, Masakatsu
supporting information, p. 526 - 529 (2018/02/10)
A direct catalytic Mannich-type reaction of α-oxygen-functionalized amides was achieved. The use of 7-azaindoline amide was crucial to facilitate direct enolization and subsequent stereoselective addition to imines in a cooperative catalytic system comprising a soft Lewis acid and Br?nsted base. The operationally simple room-temperature protocol furnished a syn-Mannich adduct with high stereoselectivity. Divergent functional group transformation of the amide moiety of the product allowed for expeditious access to enantioenriched syn-configured α-hydroxy-β-amino carboxylic acid derivatives, highlighting the synthetic utility of the present catalysis.
Copper-catalyzed borylative coupling of vinylazaarenes and N-Boc imines
Smith, Joshua J.,Best, Daniel,Lam, Hon Wai
supporting information, p. 3770 - 3772 (2016/03/22)
Cu-catalyzed three-component couplings of vinylazaarenes, B2(pin)2, and N-Boc imines are described. Oxidation of the initially formed boronate gives azaarene-containing, Boc-protected amino alcohols with reasonable to good diastereoselectivities.
Towards a General Understanding of Carbonyl-Stabilised Ammonium Ylide-Mediated Epoxidation Reactions
Novacek, Johanna,Roiser, Lukas,Zielke, Katharina,Robiette, Rapha?l,Waser, Mario
supporting information, p. 11422 - 11428 (2016/08/03)
The key factors for carbonyl-stabilised ammonium ylide-mediated epoxidation reactions were systematically investigated by experimental and computational means and the hereby obtained energy profiles provide explanations for the observed experimental results. In addition, we were able to identify the first tertiary amine-based chiral auxiliary that allows for high enantioselectivities and high yields for such epoxidation reactions.
Efficient synthesis of α-(N-Boc)aminoamides by addition of a carbamoylsilane to N-Boc-imines
Guo, Qilin,Wen, Xueping,Chen, Jianxin
, p. 8117 - 8122 (2016/11/19)
N,N-Dimethylcarbamoyl(trimethyl)silane reacted with N-Boc-imines in anhydrous benzene under catalysts-free conditions to afford N-Boc-protected α-amino amides in good yields (72-89%). The electronic property and the steric hindrance of substituent on the N-Boc-imines affected the reaction.
