titanated pyridines in a highly selective manner. The reaction can be classified into four categories: (i) a combination of an internal acetylene, a terminal acetylene, sulfonylnitrile, and the titanium reagent to yield alpha-titanated pyridines, (ii) a combination of an internal acetylene, a (sulfonylamino)acetylene, a nitrile, and the titanium reagent to yield alternative alpha-titanated pyridines, (iii)
Selective Syntheses of Metalated Pyridines from Two Different Unsymmetrical Acetylenes, a Nitrile, and a Titanium(II) Alkoxide
作者:Daisuke Suzuki、Ryoichi Tanaka、Hirokazu Urabe、Fumie Sato
DOI:10.1021/ja017766z
日期:2002.4.1
Cyclotrimerization of two different, unsymmetrical acetylenes and p-toluenesulfonylnitrile with a divalent titanium alkoxide reagent, Ti(O-i-Pr)4/2 i-PrMgCl, yielded single pyridyltitanium compounds in a highly selective manner. These metalated pyridines were confirmed by deuteriolysis to give the corresponding deuterated pyridines and underwent iodinolysis and copper-catalyzed alkylation to demonstrate
两种不同的不对称乙炔和对甲苯磺酰基腈与二价钛醇盐试剂 Ti(Oi-Pr)4/2 i-PrMgCl 的环三聚反应以高度选择性的方式产生单一的吡啶基钛化合物。这些金属化吡啶通过氘分解得到相应的氘化吡啶,并进行碘分解和铜催化烷基化以证明它们的合成效用。或者,由相同的钛 (II) 醇盐介导的炔酰胺、末端乙炔和 α-烷氧基腈的不同类型的环三聚反应再次以高度选择性的方式进行,得到具有钛化侧链的单个吡啶。
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.