Simple Molybdenum(IV) Olefin Complexes of the Type Mo(NR)(X)(Y)(olefin)

被引：43

作者：

Marinescu, Smaranda C. ^{[1
]}

King, Annie J. ^{[1
]}

Schrock, Richard R. ^{[1
]}

Singh, Rojendra ^{[1
]}

Muller, Peter ^{[1
]}

Takase, Michael K. ^{[1
]}

机构：

[1] MIT, Dept Chem, Cambridge, MA 02139 USA

来源：

ORGANOMETALLICS | 2010年 / 29卷 / 24期

基金：

美国国家科学基金会;

关键词：

IMIDO ALKYLIDENE COMPLEXES; RING-CLOSING METATHESIS; TUNGSTEN ALKYLIDENE; MECHANISTIC INVESTIGATIONS; ALKENE METATHESIS; CATALYSTS; CONTAIN; LIGAND; METAL; METALLACYCLOBUTANE;

D O I：

10.1021/om101003v

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Exposure of heptane solutions of Mo(NAr)(CHCMe(2)Ph)(Me(2)Pyr)(OAr) (1a, Ar = 2 6-diisopropylphenyl) Mo(NAr)(CHCMe(3))(Me(2)Pyr)[OCMe(CF(3))(2)] (1b) and Mo(NAr)(CHCMe(2)Ph)(Me(2)Pyr)(OSiPh(3)) (1c) to one atmosphere of ethylene for 12 h yields the ethylene complexes Mo(NAr)(CH(2)CH(2)) (Me(2)Pyr)(OAr) (2a) Mo(NAr)(CH(2)CH(2))(Me(2)Pyr)[OCMe(CF(3))(2)] (2b) and Mo(NAr)(CH(2)CH(2)) (Me(2)Pyr)(OSiPh(3)) (2c) Addition of I equiv of triphenylsilanol to a solution of 2c gives Mo(NAr)(CH(2)CH(2))(OSiPh(3))(2) (3) readily Mo(NAr)(CHCMe(2)Ph)(OTf)(2)(dme) reacts slowly with ethylene (60 psi) in toluene at 80 degrees C to give cis and trans isomers of Mo(NAr)(CH(2)CH(2))(OTf)(2)(dme) (4a) in the ratio of similar to 2(cis) 1 Addition of lithium 2 5 dimethylpyrrolide to 4a under 1 atm of ethylene produces Mo(NAr)(CH(2)CH(2))(eta(1) Me(2)PYr)(eta(5) Me(2)Pyr) (5a) Mo(NAr)(CHCMe(2)Ph)(eta(1) MesPYr)(2) (MesPyr = 2 mesitylpyrrolide) reacts cleanly with ethylene in benzene at 60 degrees C over a period of four days to give exclusively Mo(NAr)(CH(2)CH(2))(MesPyr)(2) (5b) Treatment of 5b with 2 equiv of (CF(3))(2)CHOH in ether yields Mo(NAr)(CH(2)CH(2))[OCH(CF(3))(2)](2)(Et(2)O) (6) Neat styrene reacts with 2c and 3 to generate the styrene complexes Mo(NAr)(CH(2)CHPh)(Me(2)Pyr)(OSiPh(3)) (7) and Mo(NAr)(CH(2)CHPh)(OSiPh(3))(2) (8) respectively Similarly the trans 3 hexene complex Mo(NAr) (trans 3 hexene)(OSiPh3())2 (9a) can be prepared from 3 and neat trans 3 hexene When 3 is exposed to 1 atm of ethylene the molybdacyclopentane species Mo(NAr)(C(4)H(8))(OSiPh(3))(2) (10) is generated X ray structural studies were carried out on 2c 5a 6 8 9a and 10 All evidence suggests that alkene exchange at the Mo(IV) center is facile followed by cis trans isomerization and isomerization via double bond migration In addition trace amounts of alkylidene complexes are formed that result in slow metathesis reactions of free olefins to give (e g) a distribution of all possible linear olefins from an initial olefin and its double bond isomers

引用

页码：6816 / 6828

页数：13

共 52 条

[1] Fine-tuning of molybdenum imido alkylidene complexes for the cyclopolymerization of 1,6-heptadiynes to give polyenes containing exclusively five-membered rings [J].