Alkyltriflones in the Ramberg–Bäcklund Reaction: An Efficient and Modular Synthesis of <i>gem</i>-Difluoroalkenes
作者:Yuuki Maekawa、Masakazu Nambo、Daisuke Yokogawa、Cathleen M. Crudden
DOI:10.1021/jacs.0c07924
日期:2020.9.16
of gem-difluoroalkenes through the Ramberg-Bäcklund reaction of alkyl triflones is described herein. Structurally diverse, fully-substituted gem-difluoroalkenes that are difficult to prepare by other methods can be easily prepared from readily available triflones by treatment with specific Grignard reagents. Experimental and computationalstudies provide insight into the unique and critical role of
procedure for the preparation of allylic trifluoromethanesulfones with high regioselectivity from aromatic allylicalcohols/esters and NaSO2CF3 under transition-metal-free conditions is described. A wide range of functional groups were tolerated. This is the first example to realize different types of allylicalcohols, including primary, secondary, and tertiary allylicalcohols, all of which transferred to
One‐Pot Synthesis of Allylic Sulfones, Ketosulfones, and Triflyl Allylic Alcohols from Domino Reactions of Allylic Alcohols with Sulfinic Acid under Metal‐Free Conditions
作者:Xue‐Qiang Chu、Hua Meng、Xiao‐Ping Xu、Shun‐Jun Ji
DOI:10.1002/chem.201500469
日期:2015.8.3
A metal‐free tandem procedure by using a sulfonylation reaction of aryl allylicalcohols followed by an iodobenzenediacetate (PIDA)‐promoted oxidative functionalization has been established. Allylicsulfones, γ‐ketosulfones, and triflylallylicalcohols have been constructed in a single operation. The methodology incorporates the sulfonyl (both aryl and triflyl) functionality with a simple work‐up
The synthesis and reactivity of propargylic and allylic trifluoromethanesulfinates under various conditions has been investigated. Propargylic esters readily undergo (2,3)-sigmatropic rearrangement to the corresponding allenyl trifluoromethyl sulfones, even under solvolytic conditions. An unusually facilenucleophilic addition of the solvent to the allenyl sulfone under the latter conditions has also
Described here is the R3P/ICH2CH2I-promoted dehydroxylativesulfonylation of alcohols with a variety of sulfinates. In contrast to previous dehydroxylativesulfonylation methods, which are usually limited to active alcohols, such as benzyl, allyl, and propargyl alcohols, our protocol can be extended to both active and inactive alcohols (alkyl alcohols). Various sulfonyl groups can be incorporated,
此处描述的是 R 3 P/ICH 2 CH 2 I 促进的醇与各种亚磺酸盐的脱羟基磺酰化反应。与以前的脱羟基磺酰化方法通常仅限于活性醇(如苯甲基醇、烯丙基醇和炔丙醇)相比,我们的方案可以扩展到活性醇和非活性醇(烷基醇)。可以并入各种磺酰基,例如CF 3 SO 2和HCF 2 SO 2,它们是药物化学中感兴趣的氟化基团,其安装受到越来越多的关注。值得注意的是,所有试剂都很便宜且广泛可用,并且在 15 分钟的反应时间内获得了中等到高产率。