Moschona, Fotini; Misirlaki, Christina; Karadimas, Nikolaos; Koutiva, Maria; Savvopoulou, Ioanna; Rassias, Gerasimos published the artcile< Organocatalytic Asymmetric Halocyclization of Allylic Amides to Chiral Oxazolines Using DTBM-SEGPHOS-Mechanistic Implications from Hammett Plots>, Name: 3-Bromobenzotrifluoride, the main research area is oxazoline preparation enantioselective regioselective; allylic amide chlorocyclization chiral diphosphine organocatalyst.
The intramol. halocyclization of alkenes possessing an internal heteroatom nucleophile leads to multifunctional heterocycles which are useful versatile intermediates in organic synthesis. The asym. chlorocyclization of 2-substituted allylic amides ArC(O)NHCH2C(=CH2)R (R = Ph, 4-FC6H4, pyridin-3-yl, naphthalen-1-yl, etc.; Ar = Ph, 4-MeOC6H4, 4-MeC6H4, etc.) gives access to chiral oxazolines I (X = Cl) bearing a chloromethyl moiety for further synthetic manipulation. The literature reports on this transformation involve complex syntheses of the 2-substituted allylic amides and cryogenic temperatures for achieving high enantioselectivities in the organocatalyzed halocyclization step. Based on the Heck reaction of aryl bromides ArBr (Ar = Ph, 4-CNC6H4, pyridin-3-yl, naphthalen-1-yl, etc.;) and Boc-protected allylamine or allylamine benzamides, a practical synthesis of 2-substituted allylic amides that does not require chromatog. was developed and accomplished their asym. halocyclization reaction with 24-92%ee under practical conditions (5°C, CpME) catalyzed by (S)-(+)-DTBM-SEGPHOS. In addition, using appropriately substituted substrates, Hammett plots were generated and formulated a consistent mechanism for the halocyclization reaction which involves two competing modes of formation of the haliranium intermediate whose relative kinetics are governed by the electronic properties of the substrate.
Symmetry published new progress about Aromatic amines Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 401-78-5 belongs to class bromides-buliding-blocks, and the molecular formula is C7H4BrF3, Name: 3-Bromobenzotrifluoride.
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary