139214-34-9Relevant articles and documents
Enantioselective Synthesis of α-Allyl Amino Esters via Hydrogen-Bond-Donor Catalysis
Bendelsmith, Andrew J.,Kim, Seohyun Chris,Wasa, Masayuki,Roche, Stéphane P.,Jacobsen, Eric N.
, p. 11414 - 11419 (2019/08/20)
We report a chiral-squaramide-catalyzed enantio- and diastereoselective synthesis of α-allyl amino esters. The optimized protocol provides access to N-carbamoyl-protected amino esters via nucleophilic allylation of readily accessible α-chloro glycinates. A variety of useful α-allyl amino esters were prepared, including crotylated products bearing vicinal stereocenters that are inaccessible through enolate alkylation, with high enantioselectivity (up to 97% ee) and diastereoselectivity (>10:1). The reactions display first-order kinetic dependence on both the α-chloro glycinate and the nucleophile, consistent with rate-limiting C-C bond formation. Computational analysis of the uncatalyzed reaction predicts an energetically inaccessible iminium intermediate, and a lower energy concerted SN2 mechanism.
Pd-Catalyzed C(sp3)-C(sp2) cross-coupling of Y(CH2SiMe3)3(THF)2 with vinyl bromides and triflates
Cai, Guilong,Zhou, Zhibing,Wu, Wenchao,Yao, Bo,Zhang, Shaowen,Li, Xiaofang
supporting information, p. 8702 - 8706 (2016/10/03)
Pd-Catalyzed C(sp3)-C(sp2) cross-coupling of Y(CH2SiMe3)3(THF)2 with vinyl bromides and triflates has been developed for efficient synthesis of various allyltrimethylsilanes. The cross-coupling reaction was conducted at room temperature with low catalyst loading of either Pd(PPh3)4 or Pd(PPh3)2Cl2, and exhibited high efficiency and a broad substrate scope. In combination with the cross-coupling by the Lewis-acid catalyzed Hosomi-Sakurai reaction, a novel three-component one-pot cascade reaction was then accomplished to deliver homoallylic alcohols and ethers with high regioselectivity and diastereoselectivity. The three-component reaction defined the yttrium complex as a novel one-carbon synthon, which could either trigger bifunctionalization of alkenes or link two electrophiles and would find applications in organic synthesis.
Optimisation of the allylsilane approach to C-10 deoxo carba analogues of dihydroartemisinin: Synthesis and in vitro antimalarial activity of new, metabolically stable C-10 analogues
O'Neill,Pugh,Stachulski,Ward,Davies,Kevin Park
, p. 2682 - 2689 (2007/10/03)
An optimised protocol has been developed for the coupling of dihydroartemisinin benzoate with a range of aromatic allylsilanes to provide a number of new C-10 deoxo derivatives (11a-11g) in yields ranging from 70 to 94%. These compounds were up to ten times more potent than artemisinin in in vitro tests against the chloroquine resistant K1 strain of Plasmodium falciparum. Ferrous mediated degradation of these analogues produces as the main product, a dicarbonyl formate 12, which is not seen when the same reaction is carried out with artemisinin or artemether. This finding may indicate that analogues in this class have a subtly different "antimalarial" mechanism of action.