Titanium Alkoxide-Based Method for Stereoselective Synthesis of Functionalized Conjugated Dienes
作者:Takashi Hamada、Daisuke Suzuki、Hirokazu Urabe、Fumie Sato
DOI:10.1021/ja9905694
日期:1999.8.1
hydrolysis, deuteriolysis, or iodinolysis, gave diene 8, or its bis-deuterated (>99% d2) and bis-iodinated counterparts (9 and 10), in good yields and with high selectivities. This reaction is applicable to the cross-coupling reaction of functionalized acetylenes such as 2-alkynoates and 2-alkynamides 12−18 and a variety of terminal acetylenes 24−28 to give dienes 36−50 in good yields. A terminal acetylene
Selective Preparation of Benzyltitanium Compounds by the Metalative Reppe Reaction. Its Application to the First Synthesis of Alcyopterosin A
作者:Ryoichi Tanaka、Yoshitaka Nakano、Daisuke Suzuki、Hirokazu Urabe、Fumie Sato
DOI:10.1021/ja027008o
日期:2002.8.1
divalent titanium alkoxide reagent, Ti(O-i-Pr)4/2 i-PrMgCl, reacted with propargyl bromide to give directly benzyltitaniumcompounds. The resultant benzyltitaniumcompounds underwent deuteriolysis, iodinolysis (with I2), or oxygenation (with O2 gas) to give the corresponding deuterium-labeled compounds, iodides, or alcohols, illustrating their synthetic versatility. The first synthesis of alcyopterosin A
二烷氧基钛环戊二烯由两种不同的乙炔和二价钛醇盐试剂 Ti(Oi-Pr)4/2 i-PrMgCl 制备,与炔丙基溴反应直接得到苄基钛化合物。得到的苄基钛化合物经过氘分解、碘分解(用 I2)或氧化(用 O2 气体)得到相应的氘标记化合物、碘化物或醇,说明了它们的合成多功能性。alcyopterosin A 的首次合成,一种最近分离和表征的双环芳香倍半萜类化合物,已通过这种方法实现,从乙炔和二炔的适当组合开始。
Practical preparation of N-(1-alkynyl)sulfonamides and their synthetic utility in titanium alkoxide-mediated coupling reactions
olefinic stereo-, and diastereoselective addition to aldehydes to give virtually single allyl alcohols. Alternatively, inter- or intramolecular coupling reaction between N-(1-alkynyl)sulfonamides and another acetylene or olefin with the above titanium alkoxide reagent generated the corresponding titanacycles, hydrolysis of which furnished stereo-defined (sulfonylamino)dienes or cyclic compounds.
Efficient and General Synthetic Approach to Pentasubstituted Conjugated Dienes Using Site-Selective Coupling of Cuprates with 1,4-Diiodo-1,3-alkadienes as the Key Reaction C.D. would like to thank the Japan Society for the Promotion of Science (JSPS) for financial support.
作者:Ryota Nakajima、Christophe Delas、Yuuki Takayama、Fumie Sato
Concise and Stereoselective Synthesis of Enamides and Dienamides by a Titanium-Mediated Coupling Method
作者:Ryoichi Tanaka、Shuji Hirano、Hirokazu Urabe、Fumie Sato
DOI:10.1021/ol027209x
日期:2003.1.1
Ynamide-titanium alkoxide complexes underwent hydrolysis or addition to aldehydes and ketones to give single, stereodefined di- or trisubstituted enamides in good yields. Alternatively, coupling of a variety of alkyne-titanium alkoxide complexes with terminal ynamides generated amino-substituted titanacyclopentadienes, hydrolysis or aldehyde addition of which afforded stereodefined dienamides.