Homologation of representative boronic esters using in situ generated (halomethyl)lithiums: A comparative study
作者:Raman Soundararajan、Guisheng Li、Herbert C. Brown
DOI:10.1016/0040-4039(94)88399-8
日期:1994.11
A comparativestudy of the homologation of representativeboronicesters with in situgenerated LiCH2X (X= Cl; Br; I) is presented wherein the reactivity differences arising out of the steric and electronic effects of the migrating groups, and the nature of the ester groups are determined and discussed.
Novel diastereoselective synthesis of (E)- and (Z)-allylsilanes via organoboranes
作者:Narayan G. Bhat、Wendy C. Lai、Matthew B. Carroll
DOI:10.1016/j.tetlet.2007.04.052
日期:2007.6
A simple, novel diastereoselective synthesis of both (E)- and (Z)-allylsilanes via organoboranes is developed. (E)-1-Alkenylboronate esters easily prepared from the corresponding terminal alkynes viahydroboration with dibromoborane-methyl sulfide complex followed by treatment with 1,3-propane diol readily react with trimethylsilylmethyllithium at −78 °C in methanol followed by reaction with iodine
Nickel-catalyzed coupling reaction of sterically congested cis bromides and lithium alkenylborates
作者:Yuichi Kobayashi、Yuji Nakayama、Ryo Mizojiri
DOI:10.1016/s0040-4020(97)10206-x
日期:1998.2
Lithium alkenyl borates of general structure 5 (RT=alkenyl) couple with cis bromides 1 at room temperature overnight in the presence of NiCl2(PPh3)2 as a catalyst to furnish dienes of general structure 3 with retention of the olefin geometries present in both coupling partners. By using this reaction, cis, trans dienes 3 (R=TBDMS, TES, TBDPS; R1=n-C5H11, c-C6H11, R2=H; R3=n-C5H11, Ph) and cis,cis diene
通式5的烯基硼酸锂(R T =烯基)在室温下在作为催化剂的NiCl 2(PPh 3)2存在下与顺式溴化物1偶联过夜,以提供通式3的二烯并保留存在的烯烃几何结构在两个耦合伙伴中。通过使用该反应,顺式,二烯3(R = TBDMS,TES,TBDPS; R 1=n -C 5 H 11,c -C 6 H 11,R 2= H; R3 = n -C 5 H 11,Ph)和顺式,顺式二烯3(R = TBDMS; R 1 = R 2 = n -C 5 H 11; R 3 = H)以高收率合成。