Synthesis of 2-Azaspiro[4.6]undec-7-enes from N-Tosyl-N-(3-arylpropargyl)-Tethered 3-Methylcyclohex-2-en-1-ols
摘要:
The FeCl3-promoted synthesis of 2-azaspiro[4.6]-undec-7-ene rings proceeds via ring expansion/cyclization/chlorination of N-tosyl-N-(3-arylpropargyl)-tethered 6-methylbicyclo[4.1.0]heptan-2-ols. This azaspirocyclic ring skeleton can also be obtained in one pot from the tert-butyldimethylsilyl-protected N-tosyl-N-(3-arylpropargyl)-tethered 3-methylcyclohex-2-en-1-ols and diethylzinc/diiodomethane.
Synthesis of 2-Azaspiro[4.6]undec-7-enes from N-Tosyl-N-(3-arylpropargyl)-Tethered 3-Methylcyclohex-2-en-1-ols
摘要:
The FeCl3-promoted synthesis of 2-azaspiro[4.6]-undec-7-ene rings proceeds via ring expansion/cyclization/chlorination of N-tosyl-N-(3-arylpropargyl)-tethered 6-methylbicyclo[4.1.0]heptan-2-ols. This azaspirocyclic ring skeleton can also be obtained in one pot from the tert-butyldimethylsilyl-protected N-tosyl-N-(3-arylpropargyl)-tethered 3-methylcyclohex-2-en-1-ols and diethylzinc/diiodomethane.
Facile Synthesis of Spirocyclic Ketones via Gold(I)-Catalyzed Claisen-Type Rearrangement of Cyclic 8-Aryl-2,7-enyn-1-ols
作者:Ming-Chang P. Yeh、Hui-Fen Pai、Chuen-Yo Hsiow、Yan-Rong Wang
DOI:10.1021/om900833k
日期:2010.1.11
The gold(I)-catalyzed Claisen-type rearrangement of cyclic 8-aryl-2,7-enyn-1-ols proceeds via a cationic allylic vinyl ethergold intermediate to give spirocyclic ketones. The reaction proceeded via attack of the hydroxyl group onto the gold-activated alkynes followed by [3,3]-sigmatropic rearrangement to generate the spirocyclic ketones. This transformation can be applied to the synthesis of aza-
Facile Synthesis of Azaspirocycles via Iron Trichloride-Promoted Cyclization/Chlorination of Cyclic 8-Aryl-5-aza-5-tosyl-2-en-7-yn-1-ols
作者:Ming-Chang P. Yeh、Cheng-Wei Fang、Hsin-Hui Lin
DOI:10.1021/ol300434m
日期:2012.4.6
A simple and efficient FeCl3-promoted cyclization/chlorination of cyclic tosylamine-tethered 8-aryl-2-en-7-yn-1-ols was observed. The reaction proceeded instantaneously at 23 degrees C in air to afford (Z)-4-(arylchloromethylene)-substituted azaspirocycles in good to excellent yields. This transformation can also be applied to the synthesis of spirocarbocyclic analogues from cyclic 8-aryl-2-en-7-yn-1-ols and FeCl3.
Diastereoselective Synthesis of 2-Arylmethylene-6-hydroxyspiro[4.5]deca-7-ones via FeCl<sub>3</sub>·6H<sub>2</sub>O-Catalyzed Spiroannulation/Hydride Transfer of 6-(5-Arylpent-4-yn-1-yl)-7-oxabicyclo[4.1.0]heptan-2-ols
作者:Hsin-Hui Lin、Kuan-Yi Lee、Yin-An Chen、Chi-Fan Liu、Ming-Chang P. Yeh
DOI:10.1021/jo5023266
日期:2014.12.5
In the presence of a catalytic amount of FeCl3 center dot 6H(2)O, 6-(5-arylpent-4-yn-1-yl)-7-oxabicyclo[4.1.0]heptan-2-ols underwent attack of the pendant acetylene at the iron-activated oxirane to give a vinylic carbocation. Hydride transfer from the carbinol carbon to the newly formed cation center furnished 2-arylmethylene-6-hydroxyspiro[4.5]deca-7-ones in excellent stereoselectivity and good yields.
Synthesis of 2-Azaspiro[4.6]undec-7-enes from <i>N</i>-Tosyl-<i>N</i>-(3-arylpropargyl)-Tethered 3-Methylcyclohex-2-en-1-ols
作者:Ming-Chang P. Yeh、Chia-Jung Liang、Chern-Wei Fan、Wei-Hang Chiu、Jun-Yuan Lo
DOI:10.1021/jo301764g
日期:2012.11.2
The FeCl3-promoted synthesis of 2-azaspiro[4.6]-undec-7-ene rings proceeds via ring expansion/cyclization/chlorination of N-tosyl-N-(3-arylpropargyl)-tethered 6-methylbicyclo[4.1.0]heptan-2-ols. This azaspirocyclic ring skeleton can also be obtained in one pot from the tert-butyldimethylsilyl-protected N-tosyl-N-(3-arylpropargyl)-tethered 3-methylcyclohex-2-en-1-ols and diethylzinc/diiodomethane.