A green H2O-promoted solvent-free hydroamination of electron-deficient terminal alkynes with amines has been developed. All secondary amines, including aliphatic and aromaticamines, gave the corresponding (E)-enamines in good to excellent yields, whereas primary aromaticamines afforded Z-configured products in moderate yields. Propiolates, propyn-1-ones, propynamides, and 1-(ethynylsulfonyl)-4-methylbenzene
A novel [4+1] spiroannulation of o‐ & p‐bromophenols with α,β‐unsaturated imines has been developed for the direct synthesis of a new family of azaspirocyclic molecules. Notably, several other halophenols (X=Cl, I) were also applicable for this transformation. Moreover, a catalytic asymmetric version of the reaction was realized with 1‐bromo‐2‐naphthols by using a chiral ScIII/Py‐Box catalyst. Mechanistic
已经开发了一种新颖的[4 + 1]邻和对溴苯酚与α,β-不饱和亚胺螺环合成的方法,用于直接合成新的氮杂螺环分子家族。值得注意的是,其他几种卤代酚(X = Cl,I)也适用于该转化。此外,通过使用手性Sc III / Py-Box催化剂,使用1-溴-2-萘酚实现了反应的催化不对称形式。机理研究表明,该多米诺反应是通过苯酚衍生物在其卤代位置的亲电触发的脱芳香化作用进行的,然后通过基于自由基的S RN 1机理用N-亲核试剂进行卤素置换。
Redox-Neutral Rhodium(III)-Catalyzed Chemospecific and Regiospecific [4+1] Annulation between Indoles and Alkenes for the Synthesis of Functionalized Imidazo[1,5-<i>a</i>]indoles
unit, a redox-neutral rhodium(III)-catalyzed chemo- and regiospecific [4+1] annulation between indoles and alkenes for the synthesis of functionalized imidazo[1,5-a]indoles has been achieved. Internal alkenes employed here can fulfill an unusual [4+1] annulation rather than normal [4+2] annulation/C–Halkenylation. This method is characterized by excellent chemo- and regioselectivity, broad substrate scope
利用嵌入氧化功能/离去基团的内部烯烃作为稀有和非常规的单碳单元,氧化还原中性铑(III)催化的吲哚和烯烃之间的化学和区域特异性[4 + 1]环化,用于合成功能化咪唑并[1,5- a ]吲哚已经实现。这里使用的内部烯烃可以实现不寻常的 [4+1] 环化,而不是正常的 [4+2] 环化/C-H 烯基化。该方法的特点是优异的化学和区域选择性、广泛的底物范围、良好的官能团耐受性、良好的收率和氧化还原中性条件。
Double 1,4-addition of (thio)salicylamides/thiosalicylic acids with propiolate derivatives: a direct, general synthesis of diverse heterocyclic scaffolds
ring-closure procedure to prepare a range of diverse heterocycles has been developed. In this transformation, a variety of substituted (thio)salicylamides and thiosalicylicacids occured double 1, 4-additions reaction with propiolate derivatives in the presence of inorganic base (K3PO4), as a result, benzothiazinones, benzoxazinones and benzoxathiinones were prepared in good to excellent yields respectively