Selective Alkenylation and Hydroalkenylation of Enol Phosphates through Direct CH Functionalization
作者:Xu‐Hong Hu、Xiao‐Fei Yang、Teck‐Peng Loh
DOI:10.1002/anie.201506437
日期:2015.12.14
Rh‐catalyzed direct CH functionalization reaction of enol phosphates was developed. The method is applicable to a variety of coupling partners, including activatedalkenes, alkynes, and allenes, and leads to the formation of various valuable alkenylated and hydroalkenylated enol phosphates through the action of the phosphate directing group. The versatility and utility of the coupling products were demonstrated
Novel Selective Approach to Terminally Substituted [<i>n</i>
]Dendralenes
作者:Peter Polák、Tomáš Tobrman
DOI:10.1002/ejoc.201801522
日期:2019.2.7
A methodology for the synthesis of terminally substituted [3]‐ and [4]dendralenes, as well as 2,3‐disubstituted buta‐1,3‐dienes has been prepared. This involves the preparation of 1,2‐disubstituted cyclobutenes from readily available 2‐bromocyclobutanone and the subsequent thermal ring‐opening reactions.
Preparation of Functionalized Cyclic Enol Phosphates by Halogen−Magnesium Exchange and Directed Deprotonation Reactions
作者:Fabian M. Piller、Tomke Bresser、Markus K. R. Fischer、Paul Knochel
DOI:10.1021/jo100763f
日期:2010.7.2
halogen/magnesium exchange reaction or deprotonation using TMP-derived magnesium amide bases. The resulting magnesium reagents react readily with a wide range of electrophiles like allyl bromides and acid chlorides or can be used in Pd-catalyzed cross-coupling reactions. Several optically pure enol phosphates were prepared starting from readily available d-(+)-camphor derivatives.
Cobalt-catalyzed directed C–H alkenylation of pivalophenone N–H imine with alkenyl phosphates
作者:Wengang Xu、Naohiko Yoshikai
DOI:10.3762/bjoc.14.60
日期:——
A cobalt-N-heterocycliccarbene (NHC) catalyst efficiently promotes an ortho C-Halkenylation reaction of pivalophenone N-H imine with an alkenylphosphate. The reaction tolerates various substituted pivalophenone N-H imines as well as cyclic and acyclic alkenylphosphates.
synthetically useful approach to functionalized triazoles is described via the reaction of β-carbonyl phosphonates and azides. 1,4- and 1,5-disubstituted and 1,4,5-trisubstituted triazoles can be regio- and chemoselectively accessed under mild conditions in good to excellent yields (31 examples, up to 99%). A mechanism is proposed that rationalizes the avoidance of the 4-phosphonate byproducts, which