The Synthesis and Dimerization of Transient 1-Silabutadienes

3-Methyl-1-tris(trimethylsilyl)silyl-2-butenol(1) ( 6 ) and (E)-3-Phenyl-1-tris(trimethylsilyl)silyl-2-propenol(1) ( 7 ) were prepared by the reaction of tris(trimethylsilyl)silyllithium ( 5 ) with 3,3-dimethylacrolein and (E)-cinnamaldehyde, resp. The alcohols 6 and 7 proved to be suitable precursors for the generation of the transient 1-silabutadienes (Me₃Si)₂Si = CHCH = CR¹R² 8 and 9 ( 8 : R¹ = R² = Me; 9 : R¹ = H, R² = Ph) following the principle of the modified Peterson reaction. Thus, 6 and 7 after deprotonation with excess MeLi in ether at low temperatures eliminated trimethylsilanolate and gave 8 and 9 , which were trapped by the excess organolithium reagent undergoing nucleophilic 1,2- or 1,4-addition reactions. In the absence of scavengers, e.g. when 8 and 9 were generated by treatment of 6 and 7 with stoichiometric quantities of MeLi in ether, the 1-silabutadienes dimerize in a [2 + 2] head-to-head fashion to give the 1,2-disilacyclobutanes 17 and 18 , resp., besides polymeric material. Treatment of the alcohol 6 with MeLi in tetrahydrofuran caused a 1,3-Si,O-trimethylsilyl shift affording the alkoxysilane (Me₃Si)₂SiH? CH(OSiMe₃)CH = CMe₂ 19 .     

Alcalase-catalyzed Synthesis of Novel 2,6-Dimethoxyhydroquinone-3-mercaptoacetyl-peptide Conjugates

Seven dipeptide and one tripeptide conjugates of the cytotoxic drug 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA) conjugates were prepared successfully by an alcalase-catalyzed reaction in alcohols, using DMQ-MA-X-OMe as the acyl donor and H₂N-Y-CONH₂ as the nucleophile (where X and Y are amino acids, and amino acid/dipeptides, respectively).     

2-芳氧基-1,8-邻苯二甲酰基萘的合成及光致变色性

合成了3种2-芳氧基-1,8-邻苯二甲酰基萘类光致变色化合物,通过核磁共振谱、红外光谱、质谱和元素分析确定了结构.对产物进行了荧光光谱测定,3种光致变色化合物的荧光强度和Stoke位移都较大.用紫外-可见分光光度计对其在丙酮溶液中的光致变色行为进行了测定,3种光致变色化合物在300-600 nm范围内都具有一定的光致变色性能和较大的吸光系数.     

L-(-)-肉碱的合成

探讨了以手性环氧氯丙烷为原料,对中间体进行重结晶提高光学纯度的方法合成了L-(-)-肉碱,其质量指标符合美国药典USP(24)版的要求：     

Colloidal Synthesis of Gold Semishells

This work describes a novel and scalable colloid chemistry strategy to fabricate gold semishells based on the selective growth of gold on Janus silica particles (500 nm in diameter) partly functionalized with amino groups. The modulation of the geometry of the Janus silica particles allows us to tune the final morphology of the gold semishells. This method also provides a route to fabricating hollow gold semishells through etching of the silica cores with hydrofluoric acid. The optical properties were characterized by visible near-infrared (vis-NIR) spectroscopy and compared with simulations performed using the boundary element method (BEM). These revealed that the main optical features are located beyond the NIR region because of the large core size.