Synthesis of syn and anti 1,4‐Diols by Copper‐Catalyzed Boration of Allylic Epoxides

Iterative Asymmetric Allylic Substitutions: syn‐ and anti‐1,2‐Diols through Catalyst Control

“…The boronate products were easily oxidized to give syn ‐ and anti ‐1,2‐diols. Furthermore, if doubly differentiated diols are the desired product, in situ protection with silyl triflate and lutidine4f, 17 prior to oxidation works well (Table 1, entries 1 and 5, and Scheme , 10 → 11 ). We found that the ratio of product was maintained at 46:54 ( syn : anti ) during the entire course of the reaction with a racemic mixture of catalyst 1 and optically pure alcohol substrate (Table 1, entry 9) 16…”

One‐Pot Three‐Component Catalytic Enantioselective Synthesis of Homoallylboronates

“…The synthesis of enantioenriched a-chiral organoboron compounds has received significant attention in chemical synthesis because the CÀB bond can be converted into CÀO, CÀ N, and CÀC bonds in a stereospecific fashion. [1] Thus, the design of efficient catalytic protocols for asymmetric synthesis of boron-containing compounds is of utmost interest for organic synthesis. [2,3] In this context, homoallyl-and allylboronates are highly useful since additional derivatization using the alkene moiety as well as the boron group gives rapid access to multifunctional chiral compounds.…”

Sulfinyl‐Mediated Stereoselective Functionalization of Acyclic Conjugated Dienes

“…[2,3]-Sigmatropic rearrangement of allylic sulfoxides and proposed cascadep rocesses for the synthesiso f1,4-diol and 1,4-aminoalcohol derivatives. Existing approaches to prepare unsaturated 1,4-diols rely on nucleophilic additions, [9] reductions or metathesis, [10] of adequately functionalizedp recursors and suitable transformations carried out on oxiranes, [11] dienes and alkenes. [12] In contrast, the synthesis of the related 2-ene-1,4-aminoalcohol derivatives is comparatively less well-developed involving Pd-catalyzed allylic substitutions,a lkylationso fa minoaldehydes or reductive cleavage of 1,2-oxazines obtained by [4+ +2] cycloaddition.…”