An efficient and facile method for the synthesis of a broad series of benzofurans and naphthofurans is described. The direct intramolecular cyclodehydration of aryloxyketones in the presence of titaniumtetrachloride affords the corresponding benzofurans and naphthofurans with good regioselectivity and yields.
A highly efficient enantioselective synthesis of chiral β‐aryloxy alcohols by the RuCl2[(S)‐SDP][(R,R)‐DPEN]} [(Sa,R,R)‐1a; SDP=7,7′‐bis(diarylphosphino)‐1,1′‐spirobiindane; DPEN=trans‐1,2‐diphenylethylenediamine] complex‐catalyzed asymmetric hydrogenation of racemic α‐aryloxydialkyl ketones via dynamickineticresolution (DKR) has been developed. Enantioselectivities of up to 99% ee with good to
Gem difluorocompounds as depigmenting or lightening agents
申请人:TFCHEM
公开号:US10351501B2
公开(公告)日:2019-07-16
The present invention relates to a compound having the formula (I), as well as a method for preparing such a compound, a cosmetic or pharmaceutic composition containing such a compound, and the use thereof as a depigmenting, lightening, bleaching or whitening agent and for treating pigmentation disorders, notably by topical application on the skin.