Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States.
J Am Chem Soc. 2018 Feb 28;140(8):2797-2800. doi: 10.1021/jacs.8b00499. Epub 2018 Feb 16.
Addition of one equiv of water to Mo(CAr)OCMe(CF) (2, Ar = o-(OMe)CH) in the presence of PPhMe leads to formation of Mo(O)(CHAr)OCMe(CF) (3(PPhMe)) in 34% yield. Addition of one equiv of water alone to 2 produces the dimeric alkylidyne hydroxide complex, {Mo(CAr)OCMe(CF)}(dme) (4(dme)) in which each bridging hydroxide proton points toward an oxygen atom in an arylmethoxy group. Addition of PMe to 4(dme) gives the alkylidene oxo complex, (3(PMe)), an analogue of 3(PPhMe) (95% conversion, 66% isolated). Treatment of 3(PMe) with two equiv of HCl gave Mo(O)(CHAr)Cl(PMe) (5), which upon addition of LiO-2,6-(2,4,6-i-PrCH)CH (LiOHIPT) gave Mo(O)(CHAr)(OHIPT)Cl(PMe) (6). Compound 6 in the presence of B(CF) will initiate the ring-opening metathesis polymerization of cyclooctene, 5,6-dicarbomethoxynorbornadiene (DCMNBD), and rac-5,6-dicarbomethoxynorbornene (DCMNBE), and the homocoupling of 1-decene to 9-octadecene. The poly(DCMNBD) has a cis,syndiotactic structure, whereas poly(DCMNBE) has a cis,syndiotactic,alt structure. X-ray structures were obtained for 3(PPhMe), 4(dme), and 6.
在三苯甲烷膦（PPhMe）的存在下，向 Mo(CAr)[OCMe(CF)]（1，Ar = o-(OMe)CH）中加入 1 当量的水，得到产率为 34%的 Mo(O)(CHAr)OCMe(CF)（3(PPhMe)）。单独向 2 添加 1 当量的水，生成二聚烷基氢氧化物配合物{Mo(CAr)OCMe(CF)}（dme）（4(dme)），其中每个桥接的氢氧质子指向芳氧基甲基中的一个氧原子。向 4(dme)添加 PMe，得到亚烷基氧配合物(3(PMe))，这是 3(PPhMe)的类似物（95%转化率，66%分离产率）。用二当量的 HCl 处理 3(PMe)得到 Mo(O)(CHAr)Cl(PMe)（5），然后加入 LiO-2,6-(2,4,6-i-PrCH)CH（LiOHIPT）得到 Mo(O)(CHAr)(OHIPT)Cl(PMe)（6）。在 B(CF)存在下，化合物 6 引发环辛烯、5,6-二羧酸甲酯降冰片二烯（DCMNBD）和 rac-5,6-二羧酸甲酯降冰片烯（DCMNBE）的开环复分解聚合，以及 1-癸烯的同偶联反应生成 9-十八烯。聚（DCMNBD）具有顺式、间同立构结构，而聚（DCMNBE）具有顺式、间同立构、交替结构。获得了 3(PPhMe)、4(dme)和 6 的 X 射线结构。
