Practical Synthetic Reactions for Tine Chemical Using a Divalent Titanium Reagent

我们研制的二价钛试剂可由Ti（O-I-Pr）_4和两当量的I-PrMgCl制备，它无毒、价廉、反应活性多样。因此，该试剂已成为许多合成化学家广泛使用的试剂。进一步研究使用该试剂的反应开辟了以下新的有效合成方法：1）制备1α的实用合成方法，25-二羟基维生素D_3的合成，其中双不饱和化合物的环化反应是关键反应由光学活性烯丙基和炔丙基化合物合成手性烯丙基和烯丙基钛试剂的方法及其合成应用。3）由内乙炔和末端乙炔与试剂的金属化Reppe反应的发展，其允许容易地获得苯和吡啶衍生物。4）制备1，4-二碘-1，3-链二烯的实用方法及其用于合成多取代共轭达因和π-共轭线性低聚物的用途。

A divalent titanium reagent developed by us which can be prepared from Ti (O-I-Pr)_4 and two equivalents of I-PrMgCl is non-toxic and inexpensive, and has versatile reactivity. The reagent therefore, has become widely used by many synthetic chemists.Further study of the reactions using the reagent opens up new efficient synthetic methods mentioned below.1) Practical synthetic method for preparing 1α, 25-dihydoxy-vitamin D_3 in which cyclization of bis-unsaturated compounds mediated by the reagent is a key reaction.2) Synthetic method of chiral allyl and alleyl titanium reagent from optically active allyl and propargyl compounds, respectively, and their synthetic utilization.3) Development of metalative Reppe reaction from internal and terminal acetylene and the reagent, which allows easy access to benzene and pyridine derivatives.4) Practical method to prepare 1,4-diiodo-1,3-alkadienes and their utilization for synthesizing polysubstituted conjugated dynes and π-conjugated linear oligomers.