Synthesis of molybdenum olefin metatheses catalysts through protonation reactions

The attempted syntheses of molybdenum imido alkylidene complexes of the type Mo(NArc,)(CH-t-Bu)[Biphen] and Mo(N-2-CF3C6H4)(CHCMe2Ph)[Biphen] (Biphen2 = 3,3'-di-t-butyl-5,5',6,6'-tetramethyl- 1,1'-biphenyl-2,2'-diolate) from Mo(NArcl)(CH-t-Bu)(OTf)2(dme) and [Biphen]K2 have sporadically afforded mixtures containing the desired products along with the corresponding amido alkylidyne complexes, Mo(NHArcl)(C-t-Bu)[Biphen] and Mo(NH-2-CF3C6H4)(CCMe2Ph)[Biphen], respectively. The reaction of [Biphen]K2 with Mo(NArc,)(CH-t-Bu)(OTf)2(dme) and 10 equivalents of triethylamine reproducibly gave Mo(NHArc,)(C-t-Bu)[Biphen] in 40% yield. An X-ray crystal structure of a related complex, Mo(NHArc,)(CCMe2Ph)[S-Biphen] confirmed the proposed structure and also revealed that one ortho chloride approaches within 2.93 A of the metal approximately trans to the alkylidyne ligand. Attempts to prepare three other amido alkylidyne complexes in an analogous manner from Mo(NR")(CH-t-Bu)(OTf)2(dme) (NR" = N-2-CF3C6H4, N-2,6-i-Pr2C6H5, N-2,6-Me2C6H5) with [Biphen]K2 in the presence of 10-20 equivalents of triethylamine failed.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2006

Author dc:creator

• Sinha, Amritanshu

Advisor dc:contributor.advisor

• Richard R. Schrock.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/36262
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/36262

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/36262