143917-84-4Relevant academic research and scientific papers
Concerning the 1,5-stereocontrol in tin(iv) chloride promoted reactions of 4- and 5-alkoxyalk-2-enylstannanes: Trapping intermediate allyltin trichlorides using phenyllithium
Hobson, Lindsay A.,Thomas, Eric J.
, p. 7510 - 7526 (2012/11/06)
Transmetallation of the 5-benzyloxy-4-methylpent-2-en-1-yl(tributyl)- and -(triphenyl)stannanes 1 and 8 using tin(iv) chloride generates an allyltin trichloride that reacts with aldehydes to give (Z)-1,5-anti-6-benzyloxy-5- methylhex-3-en-1-ols 2. The allyltin trichloride believed to be the key intermediate in these reactions has been trapped by phenyllithium to give anti-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 9. Transmetallation of this anti-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 9 generated an allyltin trichloride that reacted with aldehydes to give the (Z)-1,5-syn-6-benzyloxy-5-methylhex-3-en-1-ols 23 and was trapped by phenyllithium to give syn-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 24. Similar stereoselectivity was observed for tin(iv) chloride promoted reactions of this syn-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 24 with aldehydes and with phenyllithium. The allyltin trichlorides generated by transmetallation of 4-hydroxy- and 4-benzyloxy-pent-2-enyl(triphenyl)stannanes 34 and 35 were similarly trapped by phenyllithium to give 4-hydroxy- and 4-benzyloxy-pent-1-en-3-ylstannanes 36 and 37 whose configurations were established by correlation with known compounds. This work confirmed the configurations of the intermediate allyltin trichlorides involved in tin(iv) chloride promoted reactions of 4- and 5-alkoxypent-2-enylstannanes with aldehydes and showed that the high levels of remote stereocontrol were due mainly to kinetically controlled transmetallation. A fuller mechanistic scheme is proposed for the reactions in the 5-benzyloxy-4-methylpent-2-enylstannane series together with relevant 119Sn NMR data.
Effective 1,5-, 1,6- and 1,7-remote stereocontrol in reactions of alkoxy- and hydroxy-substituted allylstannanes with aldehydes
Carey, John S.,MacCormick, Somhairle,Stanway, Steven J.,Teerawutgulrag, Aphiwat,Thomas, Eric J.
, p. 3896 - 3919 (2011/06/26)
Alk-2-enylstannanes with 4-, 5- and 6-alkoxy- or -hydroxy-substituents are transmetallated stereoselectively with tin(iv) halides to generate allyltin trihalides which react with aldehydes to give (Z)-alk-3-enols with useful levels of 1,5-, 1,6- and 1,7-stereocontrol. Alk-2-enylstannanes with a stereogenic centre bearing a hydroxy or alkoxy group at the 4-, 5- or 6-position, react with overall (Z)-1,5-, 1,6- and 1,7-syn-stereoselectivity with respect to the hydroxy and alkoxy substituents. The analogous reactions of alkoxy- and -hydroxyalk-2-enylstannanes with a methyl bearing stereogenic centre at the 4- or 5-position react with overall (Z)-1,5- and 1,6-anti-stereoselectivity with respect to the hydroxy and methyl substituents.
1,5-Stereocontrol in reactions of 5-benzyloxy-4-methylpent-2-enyl bromides with aldehydes mediated by Bi(0): Synthesis of aliphatic compounds with 1,5-syn-related methyl groups
Donnelly, Sam,Thomas, Eric J.,Fielding, Mark
, p. 6779 - 6782 (2007/10/03)
Treatment of the 5-benzyloxy-4-methylpent-2-enyl bromide 6 with the low valent bismuth species formed by reduction of bismuth(III) iodide with zinc powder generates an intermediate, which reacts with aldehydes with useful levels of 1,5-stereocontrol in favour of the 1,5-anti-(E)-isomers 4. These products were used to prepared aliphatic compounds with 1,5-syn-related methyl groups.
Remote asymmetric induction in reactions of 5-alkoxyalk-2-enylsilanes and aldehydes promoted by tin(IV) chloride
Brain, Christopher T.,Thomas, Eric J.
, p. 2387 - 2390 (2007/10/03)
Following observations on remote asymmetric induction using allylstannanes, 5-benzyloxy-4-methylpent-2-enylsilanes are also found to react with aldehydes with modest levels of 1,5-induction after treatment with tin(IV) chloride. Transmetallation to give intermediate allyltin trihalides may be involved.
15-asymmetric induction in reactions between (alkoxyallyl)stannanes and aldehydes: Influence of the Lewis acid and o-substituent
Carey, John S.,Coulter, Thomas S.,Thomas, Eric J.
, p. 3933 - 3934 (2007/10/02)
The influence of the Lewis acid and the O-substituent on the efficiency of the remote asymmetric induction observed in reactions between (alkoxyallyl)stannanes and aldehydes has been investigated.
