A series of functionalized 2,3-dihydro-1,4-benzoxazines were obtained in moderate to excellent yields via domino [5 + 1] annulations of 2-halo-1,3-dicarbonyl compounds 2 with imines 1 under mild conditions and the application of this method in the synthesis of bioactive analogues, such as functionalized tetracyclic-1,4-benzoxazines which contain two new heterocyclic rings and one quaternary carbon
Highly Efficient Synthesis of Homoallylamines from Aldimines with Allylstannane Promoted by MgI<sub>2</sub> Etherate
作者:Xingxian Zhang、Shenghui Hu、Junchen Shi
DOI:10.3184/030823410x12756737135354
日期:2010.6
We describe a mild and efficient procedure for the synthesis of homoallylamines by addition of allyltributylstannane to aldimines with promoted by MgI2 etherate (MgI2•(OEt2)n) in good to excellent yields.
The asymmetric Povarov reaction with α‐alkyl styrenes as dienophiles was catalyzed by an N,N′‐dioxide L4–Sc(OTf)3 complex. Enantiopure tetrahydroquinoline derivatives with a quaternary stereocenter at the C4 position were synthesized for the first time. A wide variety of α‐alkyl styrenes and N‐aryl aldimines were tolerated in the reaction, to give excellent diastereo‐ (up to 99:1 d.r.) and enantioselectivities
Rhodium(II) catalyzed multi-component reactions of aryldiazoacetates with titanium(IV) isopropoxide and imines
作者:Xu Zhang、Na Zhang、Xin Guo、Liping Yang、Wenhao Hu
DOI:10.1016/j.tet.2009.07.049
日期:2009.9
Rh2(OAc)4 catalyzed diazo decomposition of aryldiazoacetates in the presence of titanium(IV) isopropoxide generated oxonium ylide intermediates. Trapping of the oxonium ylide intermediates with imines occurred subsequently via a nucleophilic addition. The three-component reaction of aryldiazoacetates, titanium(IV) isopropoxide, and imines gave α-alkoxyl-β-amino acid derivatives with C–N/C–C bond formation
An enantioselective bisvinylogous Mannich reaction of silyl ketene acetal with aldimines has been realized by using a chiral N,N′‐dioxide/Tm(OTf)3 complex as catalyst, providing an effective method to synthesize chiral ζ‐amino‐α,β,γ,δ‐unsaturated carbonyl compounds.