40203-74-5Relevant articles and documents
Complementary regioselective cyclopropyl ring openings of 6- formyl-spirobicyclo[5.2]octane mediated by TMSC1 and TBAI
Huang, He,Forsyth, Craig J.
, p. 16341 - 16348 (1997)
Absolute control over the regioselectivity of trimethylsilyl halide-induced cyclopropane fragmentation of a spirofused cyclopropyl carboxaldehyde has been achieved by simply varying the reaction stoichiometry and the nature of the halide. Treatment of 6-formyl- spirobicyclo[5.2]octane with a large excess of TMSC1 gave 3-(1- chlorocyclohexyl)propanal (84% yield), whereas 2-(1- iodomethylcyclohexyl)ethanal (86% yield) was obtained using 10 equivalents each TMSC1 and n-Bu4NI (TBAI). Use of only a moderate excess of TMSC1 or TMSC1 and TBAI gave the rearranged product 3-(1- cyclohexenyl)-propanal.
Pd-catalyzed regioselective C?H alkenylation and alkynylation of allylic alcohols with the assistance of a bidentate phenanthroline auxiliary
Hirano, Koji,Miura, Masahiro,Xu, Shibo
supporting information, p. 9059 - 9064 (2020/12/02)
A Pd-catalyzed regioselective C?H alkenylation of allylic alcohols with electron-deficient alkenes has been developed. The key to success is the introduction of bidentately coordinating phenanthroline directing group, which enables the otherwise challenging and regioselective C?H activation at the proximal alkenyl C?H bonds over the conceivably competitive allylic C?O bond activation. The same Pd/phenanthroline system is efficient for the C?H alkynylation of allylic alcohols with alkynyl bromides.
Chemical assembly systems: Layered control for divergent, continuous, multistep syntheses of active pharmaceutical ingredients
Ghislieri, Diego,Gilmore, Kerry,Seeberger, Peter H.
supporting information, p. 678 - 682 (2015/03/04)
While continuous chemical processes have attracted both academic and industrial interest, virtually all active pharmaceutical ingredients (APIs) are still produced by using multiple distinct batch processes. To date, methods for the divergent multistep continuous production of customizable small molecules are not available. A chemical assembly system was developed, in which flow-reaction modules are linked together in an interchangeable fashion to give access to a wide breadth of chemical space. Control at three different levels - choice of starting material, reagent, or order of reaction modules - enables the synthesis of five APIs that represent three different structural classes (γ-amino acids, γ-lactams, β-amino acids), including the blockbuster drugs Lyrica and Gabapentin, in good overall yields (49-75%).
