Oxidation of organometallic compounds (RM, M = Li, MgBr, ZnBr, CuCNLi, Cu(R)CNLi2) with tBuOOLi, Ti(OiPr)4-mediated with tBuOOH, and with O2, to give alcohols (ROH).: Are radicals R• involved?
Oxidation of organometallic compounds (RM, M = Li, MgBr, ZnBr, CuCNLi, Cu(R)CNLi2) with tBuOOLi, Ti(OiPr)4-mediated with tBuOOH, and with O2, to give alcohols (ROH).: Are radicals R• involved?
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DOI：
10.1016/s0022-328x(00)00596-9
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发表时间：
2001-04-01
影响因子：
2.3
通讯作者：
Boche, G
中科院分区：
文献类型：
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作者：
Möller, M;Husemann, M;Boche, G
有机化合物（RM，M=Li，MgBr，ZnBr，Cu（CN）Li，CuR（CN）Li-2）用（BuOOLi）-Bu-t（或PhCMe 2 OOLi）（方法A）氧化成相应的醇（ROH），产率良好至非常好。在RM，M = Li，MgBr和ZnBr的情况下，这种氧化作用对于质子体系Ti（（OPr）-Pr-1）（4）+（BuOOH）-Bu-t（方法B）也很有效。用构型稳定的顺式和反式环丙基金属化合物（分别为顺式和反式1-M）进行的立体化学研究表明，RM（M = Li，MgBr）与（BuOOLi）-Bu-t（方法A）和Ti（（OPr）-Pr-i），+（BuOOH）-Bu-t（方法B）的反应遵循亲核试剂RM在亲电（尽管是阴离子！）（BuOOLi）-Bu-t（TiX 3）的氧原子，得到ROM（分离为酯2），保留R处的构型。与此相反，用二氧O-2的氧化（方法C）在环丙基醇ROH（RM，M = Li，MgBr）中发生立体化学损失，并且在RM，M = Cu（CN）Li，CuR（CN）Li-2的情况下另外形成环丙基二聚体R-R 3。这是由于从RM到O-2的电子转移和中间自由基R度的快速异构化（二聚化）。RM铜酸盐，M = Cu（CN）Li，CuR（CN）Li，用于电子转移反应的高趋势也通过在ROH形成中立体特异性的一些损失和一些二聚体3形成来指示，即使使用氧化剂（BuOOLi）-Bu-t（方法A）。(C)2001 Elsevier Science B. V.保留所有权利。
Organometallic compounds (RM, M=Li, MgBr, ZnBr, Cu(CN)Li, CuR(CN)Li-2) are oxidized with (BuOOLi)-Bu-t (or PhCMe2OOLi) (method A) to the corresponding alcohols (ROH), in good to very good yields. This oxidation works also well with the protic system Ti((OPr)-Pr-i)(4) + (BuOOH)-Bu-t (method B) in the case of RM, M = Li, MgBr and ZnBr. Stereochemical studies with the configurationally stable cis- and trans-cyclopropyl metal compounds, cis- and trans-1-M, respectively, show that the reactions of RM, M = Li, MgBr, with (BuOOLi)-Bu-t (method A) and Ti((OPr)-Pr-i), + (BuOOH)-Bu-t (method B) follow a S(N)2-type pathway of the nucleophile RM at the electrophilic (although anionic!) oxygen atom of (BuOOLi)-Bu-t(TiX3) to give ROM (isolated as the esters 2) with retention of configuration at R. In contrast, the oxidations with dioxygen O-2 (method C) occur with loss of stereochemistry in the cyclopropyl alcohols ROH (RM, M = Li, MgBr), and additional formation of cyclopropyl dimers R-R 3 in the case of RM, M = Cu(CN)Li, CuR(CN)Li-2. This is due to facile electron transfer from RM to O-2 and fast isomerization (dimerization) of the intermediate radicals R degrees. The high tendency of RM cuprates, M = Cu(CN)Li, CuR(CN)Li, for electron transfer reactions is also indicated by some loss of stereospecificity in the formation of ROH, and some dimer 3 formation, even with the oxidant (BuOOLi)-Bu-t (method A). (C) 2001 Elsevier Science B.V. All rights reserved.