Synthesis of Spirobicyclic Pyrazoles by Intramolecular Dipolar Cycloadditions/[1s, 5s] Sigmatropic Rearrangements
نویسندگان
چکیده
منابع مشابه
Sigmatropic rearrangements in 5-allyloxytetrazoles.
Mechanisms of thermal isomerization of allyl tetrazolyl ethers derived from the carbocyclic allylic alcohols cyclohex-2-enol and 3-methylcyclohex-2-enol and from the natural terpene alcohol nerol were investigated. In the process of the syntheses of the three 1-aryl-5-allyloxytetrazoles, their rapid isomerization to the corresponding 1-aryl-4-allyltetrazol-5-ones occurred. The experiments showe...
متن کاملDoubly diastereoselective [3,3]-sigmatropic aza-Claisen rearrangements.
The doubly diastereoselective [3,3]-sigmatropic aza-Claisen rearrangement of silylketene aminals derived from 5-substituted (3S,4E,alphaR)-1-benzyloxy-3-[N-acyl-N-(alpha-methylbenzyl)amino]pent-4-enes furnishes 2,3-disubstituted (R)-N-alpha-methylbenzyl (2S,3R,4E)-7-benzyloxyhept-4-enamides in >90% de under the "matched" control of both stereogenic centres. Rearrangement of the "mismatched" dia...
متن کاملRecent Advances in Asymmetric [3,3]-Sigmatropic Rearrangements
Synthesis 2003, No. 7, Print: 20 05 2003. Art Id.1437-210X,E;2003,0,07,0961,1008,ftx,en;E08002SS.pdf. © Georg Thieme Verlag Stuttgart · New York Abstract: The synthesis of new complex structures is still a challenge in preparative organic chemistry. Focusing on the generation of defined stereogenic centers, the [3,3]-sigmatropic rearrangements are known as reliable reactions. Always, a highly o...
متن کاملSynthesis of 1,3,5-tri-substituted pyrazoles promoted by P2O5.SiO2
Silica supported phosphorus pentoxide (P2O5·SiO2) is an efficient catalyst for synthesis of 1,3,5-substituted pyrazoles via the condensation of 1,3-diketones and hydrazines. Simplicity of procedure, mild condition, being solvent-free, high yields, and easy workup are some advantages of this protocol.
متن کاملSynthesis of 1,3,5-tri-substituted pyrazoles promoted by P2O5.SiO2
Silica supported phosphorus pentoxide (P2O5·SiO2) is an efficient catalyst for synthesis of 1,3,5-substituted pyrazoles via the condensation of 1,3-diketones and hydrazines. Simplicity of procedure, mild condition, being solvent-free, high yields, and easy workup are some advantages of this protocol.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Organic Letters
سال: 2019
ISSN: 1523-7060,1523-7052
DOI: 10.1021/acs.orglett.9b02124