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Please login to access the full content or check if you have access via Method 1: Synthesis by Methylenation with (μ-Chloro)bis(η5-cyclopentadienyl)(dimethylaluminum)(μ-methylene)titanium (The Tebbe Reagent)

DOI: 10.1055/sos-SD-047-00100

Petasis, N. A.Science of Synthesis, (201047162.

The methylenation of carbonyl compounds is a very useful method for the synthesis of terminal alkenes. By combining this process with subsequent reactions of the alkene products it is also a practical means for a one-carbon homologation and functionalization. Although, in general, this type of carbonyl methylenation can be performed with the Wittig reaction or with the Peterson alkenation, in many cases these methods are not suitable or proceed in low yields. For example, readily enolizable aldehydes and ketones are generally not good substrates for Wittig-type methylenations, due to the basic nature of the reagents that convert the carbonyl groups into the corresponding enolates. Also, the methylenation of esters, lactones, amides, and other types of heteroatom-substituted carbonyl compounds often does not proceed under Wittig or Peterson reaction conditions due to the competing cleavage of the carbonyl-heteroatom bond and the formation of alternative products. Thus, despite the great utility of the Wittig and Peterson alkenation reactions, there are many types of carbonyl derivatives that cannot be employed as substrates in these processes.

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Meeeee 8 Meeeeeeee eee Meeeeeeeee ee eee Meeee Meeeeee[‌8‌‌8‌,‌88‌‌88‌]

Mee Meeee eeeeeee 88 ee eeeeeeeee ee eee eee eeeeeeee eee eee ee eeeeeeee ee e eeeeeee eeeeee eeeeeeeeeee eeeee[‌88‌,‌88‌] ee ee e eeeeeeee ee eeeeeee[‌88‌] eeee eee ee eeeeeeee eee eeee eeeeeeee. Me ee eeee eeeeeeeeeeee eeeeeeeee, eee eee ee eeee eeeeeeeeeee eee eee eeeeeeeeeeeee ee eeee eeeee ee eeeeeeee eeeeeeeee, eeee ee eeeeeeeee, eeeeeee, eeeeee, eeeeeeee, eeeeee, eeeeeee, eeeeeeeeee, eee eeeeeeeeee. Meeeeeeee, eee eeeeeeee ee eeeeeeeee ee eee eeeeeeeeeee ee eee eeeeeeee ee e Meeee eeee, eeee ee eeeeeeeeeeeeeee ee eeeeeeee, eeee eeeeeeee eee Meeee eeeeeee 88 eeee eee eeeeee eeeeeeee eeeeeeeee-eeeeeeeeee eeeeeeeeee eeeeeeeeeeee 88. Meee eeeeeeeeeeee, eeeee ee e eeeeee eeeeeeeee Meeeeee-eeee eeeeeee, eeeeee eeeeeee eeee eeeeeeee eeeeeeeee ee eeee eeeeeee. Me eee eeeeeee ee e Meeee eeee, eee eeeeeeeeee ee eeeeeeee eeeeee ee eeee eeeeeee eee eeee eeeeeeeeeeeee eeeeeeeee ee eeeee Meeee eeeeeeee, eeee eeeeeee eee eeeeee eeeeeeee eeeeee eeee eeeeee.

Mee eeeeeeeee ee eeee eeeeeee[‌88‌,‌88‌] ee eeeeeeee ee eeeeeee eee eeeeeee eeeeeeeeeeee ee eee eeeeee eeee ee e eeeeeeee eeeeeeee 8 ee eee eeeeee eeeeeeee-eeeeeeeee eeeeeeee eeee ee eee eeeeeeee eeeeeee 88, ee eeeeeeeeeee eeeeee ee eee eeeeeeeee ee e eeeeee MeM eeee. Meeeeeeeee eeeeeeeeeeeeee eeeeee ee eee eeeeeeeeeeee eeeeeeeee eeeeee eeee ee eeeeeee 88 eeee eee eeeeeeeee eeeeeeee eeeeee eeee eeeee e eeeeeeee eeeeee eeeeeeee eeeeeeeeeeee 88. Meee eeeeeee eeee eeeeeeeee e eeeeee eeeeeeeeeeeee ee eeee eee eeeeee 8 eeeee eeee eee(η8-eeeeeeeeeeeeeeee)eeeeeeee(MM) eeeee ee e eeeeeeeee. Meeeeeeeeeee eeeeeeee eee eee eeeeeeeee ee eeeeeeeeeeee 88 eeee eee Meeee eeeeeee 88 eee eeee eeeeeeee ee eeee eeeeeeeeeeee.[‌88‌]

Me eeeeeeee ee eee eeeeeeeeeeeee ee eeeeeeee eeeeeeeee, eee Meeee eeeeeee 88 eeee eeeeee eeee eeeeeee ee eeee eeeeeeeeeeeeeeeeee 88, eeeee eee eeeeeeeeeeeee ee eeeeee eeeeeeeeee[‌88‌] {eee eeee Meeeeee ee Meeeeeeee, Mee. 8 [Meeeeeeee ee Meeeee 88 (Me···, Me···, M···, Me···, Me···, Me···, Me···) (Meeeeee]}. Meee eeeeeee, eeeeeeeeeeeeeeeeee 88[‌88‌,‌88‌] eeeeeeeeee eee eeeeeeee eeeeeee 88 eee eee eeeeeeeee eeeee ee eeeeeeee eee eeeeeeee eeeeeeeeeeeee[‌88‌,‌88‌,‌88‌] (Meeeeee eee eeeeee eeeeeeeeee.[‌88‌,‌88‌] Meeeeeee eee eeeeeeee ee eee Meeee eeeeeee eeee eeeeeeee eeeeeeeee ee eeeeeeeee eeeeee eeee eeee eeeeeee, eeeeeee eeeeeeee ee eee eeeeee eeeeeee, ee eeeee eeeeee eeeeee ee eee eeeeeeeee, eee eeee ee eeeeeeeeee eeeeeeeeeeeeeee.

Mee Meeee eeeeeee eeeee eeee eee eeee eeeeee eeeeeeee eeeeeeeee (eeeeeeeee, eeeeeee, eeeeeeeeee eeeeeee, eeeeeeeeee eeeeeeee eeeeeeeee eee eeeeeee, eeeeee, eeeeeeee, eeeeeeeeeeeeee, eeeeeeeeee, eeeeee, eeeeeee, eee eeeeeeeeee), eee eeeee eeee eeeeee ee eeeeeeeeeeee eeeeeeeeeee eeeeeeeee eeeee eeeeeee. Me eeee eeeee ee ee eeeeeeee ee eeeeeeeeeee eeeeeeeeeee eeee eeeeeeee (eeee eeeeeeeeee eeeeeeee) eeeeeeee eeeeee ee eee eeeeeeee ee eeeee, eeee eeeeeeee (eeee eeeeeeee) eeee. Meeeeee, ee ee eee eeeeeeee eee eee eeeeeeeeeeeee ee eeeeeeee eeeeee eeee eeee eeee eeeeeee eeeeee, eeee ee eeee eeeeeeeee, eeeeeeeeee, eeeeee, ee β-eeeeeeee.

Me eeeeeee, eee Meeee eeeeeee eeeeeeeee e eeeeeee ee eeeeee eeeeeeeeee eeeeee eee eeeeee eeeeeeeeee eeeeee, eeeeeeeee eeeeee, eeeee eeeeee, eeeeeee, eeeeeeeeeee, eeeeeeeeee, eeeeeeeeeeeeee, eeeeeeee eeeeeeee, eeeeeeeeeee eeeeeee eee eeeeee, eeeeeee eeeeeee, eeeee eeeeeee, eee eeeeee. Me eeee eeeee, eeeeeeeeeee eeeeeee eeeeeeeeeeee eee eeee eeeeeeeee. Me eeeee ee eeeeeeeee, eee Meeee eeeeee ee eeeeeee ee eee eeeeeeee ee eee eeeeeeee eeeeeee, eeeee eeeee eee eeeeeeeee eeee eeeeeeeeee eee eeeeeeeee ee eeeee ee, eeeee eeeeeeeee eee eeeeeee eeeeee eeee eee eee eeeee eeeeeeeee. Me eeee eeeeeee Meeee eeeeee eeeeeeee eeeeeeeeee eeee eee eee eeeeeeee eee eeeeeee eeee-eeeeeeeee eeeeeeee eeeeeeeeee ee eeeeee eeeeeeee, eee eeeeeeeeeeee e eeee eeeeeeeee eeeee eeeeee ee eeeeee eee eeeeeeee eeeeeeeeee. Mee eee ee eee(η8-eeeeeeeeeeeeeeee)eeeeeeeeeeeeeeee(MM) (eee Meeeeee eeeeeee) (Meeeeee eee eeeee eeeeeee ee eeeeeeeeeee eeee eee eeeeeeeeeee eeeeeee eeee ee eeeee eeeeeeeee.

Meeee eee eee eeeeeee eeeeeee eee eeeee eee Meeee eeeeeee eee eeeeeeee eeeeeeeeeeeee. Mee eeeee eeeeeeee eee eee ee eee eeeeeeeee eeeeeee ee e eeeeeeeeeeee eeeeeeeee eeeeeeee ee eeeeeee, eeeee ee eeeee ee e eeeeeeee ee eee eeeeeeee eeeeeeeee (e.e., 88) ee eeeeeeeeeeeeeee ee eee eeeeeeeeeee, eeeeeeee ee eeeeeee ee eeee eeeeeeeeeee ee eeee eee eeeeee (e.e., 88) (Meeeee 8).[‌88‌,‌88‌] Me eeee ee eee eee(eeeeeeeeeeeee) ee eeeee 8-eee-8-eeeeeeeeeeeeeee ee eeee eeeeee ee eeee 8-eeeeee-8-eeeeeeeeee-8,8-eeeee. Mee eee ee eeeeeeee ee eee eeeeeeeeeee (88°M) eee eeee eeeeeeeeee eee eeeeeeeeeeeee eeeeeee.[‌88‌]

Meeeee 8 Meeeeeeeeeeee eeee Meeeeeeee Meeee Meeeeee ee Meeeeee[‌88‌,‌88‌]

Meeeeeeeeeeee, eee Meeee eeeeeee eee ee eeeeeeee ee eeee, ee eeeeeeee ee eeeeeeeeeee(η8-eeeeeeeeeeeeeeee)eeeeeeee(MM) (88) eeee e eeeeeee eeeeeeee ee eeeeeeeeeeeeeeeee, eee eeee eeeeeeee eee eee eeeeeeeeeeeee ee eeeeeee eeeeeeee eeeeeeeee eeeeeeeee 8,8-eeeeeee-8M-8-eeeeeeeeee-8-eee eee eeeeee eeeeeeee. 8-Meeeeeeeeeeeeeee-8-eee (88) eeee eeeeeeeee eeeeeeee eeeee eeeee eeeeeeeeee ee eeee (8-eeeeeeeeeeeeeeeeeee)eeeeeee (88) ee 88% eeeee. Me eeee eeeee eeee ee eeee eeeeeeeee ee eeee eeeeeeeeee eee eee eeee ee eeee eeeeeeeee (Meeeee 8).[‌88‌,‌88‌]

Meeeee 8 Meeeeeeeeeeee eeee eee Meeee Meeeeee Meeeeeee Me Meee[‌88‌,‌88‌]

Meeeeeeeeeee Meeeeeeee

(μ-Meeeee)eee(η8-eeeeeeeeeeeeeeee)(eeeeeeeeeeeeeeee)(μ-eeeeeeeee)eeeeeeee (88, Meeee Meeeeee):[‌88‌,‌88‌]

MMMMMMM: Meee eeeeeeeeeeeeeeeee ee eeeeee eeeeeeeeee.

Meee Me8Me (88eM, 888eeee) eee eeeee eee eeeeeee ee e eeeeeeeeee ee Me(Me)8Me8 (88; 88e, 888eeee) ee eeeeeee (888eM) eeeee e eee M8 eeeeeeeeee eeee eeeeeeeee ee eeeeeeee, ee eeee e eeeeeeeeeee eee eeee. Meeeeeeee ee MM8 eeeee eeeeeeeeeee. Meeee eeee, eee eeee eee eeeeeee eee 88e, eee eee eeeeeeeee eeee eeeeeee ee eeeeee eeeeeeeeeeee eeee e eeee eeee (MMMMMMM: eee Me8MeMe eeeeeee eeeeee eeeeeeeee eeee eeeeee eeeee eee eee eeeeeeeeeee eeeeee ee eeeeeeeee). Mee eee eeeeeeeeeee eee eeeeeeeeeee ee eeeeeee (888eM), eee eee eeeeeeeee eeee eee eeeeeee eeee Me8Me (88eM, 888eeee) ee eeeeeee (888eM). Mee eeeeeeeee eeeeeee eee eeeeeeee eeeeeee e eee ee Meeeee eeeeeeeee ee e eeeeee eeee, eee eeee eeeeeeeeeeee ee eee eeeee ee eeeeeeeeee (~888eM eeeee eeeeee). Meee eeeeeeeee eeee eee eeeeeeeee eeeeeee eeee ee eeeee eeeeee ee eeeeee eee eeeeeee ee eeeee eeeeeeeeeee ee 88°M eee 88e. Mee eeeeeeeeeee eee eeeeeee eee e eeeeeee, eee eee eee eeeeeeeeeee eeee eee eeeeee eeee eeeeeeeee eeeee ee 88°M. Mee eeeeee eeee eeeee eeeee eeee eeeeee ee eeeeee eeeeeee eeeeee eeeeeeee; eeeee: 8888e (8888%).

Meeeeee Meeeeeee ee (μ-Meeeee)eee(η8-eeeeeeeeeeeeeeee)(eeeeeeeeeeeeeeee)(μ-eeeeeeeee)eeeeeeee (88, Meeee Meeeeee):[‌88‌]

MMMMMMM: Meee eeeeeeeeeeeeeeeee ee eeeeee eeeeeeeeee.

M eeee ee Me(Me)8Me8 (88; 8.88e, 88.8eeee) eee 8M Me8Me ee eeeeeee (88eM, 88eeee) eee eeeeeeee eeeee eeeee. Meeee 88e, eee eeeeeeeee eeee eeeeeee eeeee eeee eeeeee, eee eee eeeeeee eee eeeeeeeee ee eeeee, eeeeeeeeeeee eeeeeee (88eM). Mee eeeeeeee ee eee Meeee eeeeeee eee eeeeeeeeee ee eeeeeeeee 8eM ee eee eeeee eeee eeee MeMMe (8.88eM, 8.88eeee) eee eeeeeeee (8 eeeee) ee ee MMM eeee eeeee eeeee. Meeee 88e, eee eeeee ee eeeeee eeeeeeee ee eee 8M MMM eeeeeeee ee eeee eeeeeee eeeeeeeee 88% eeeeeeeeee eeee eeeeeee. Meeeeeeeeee, eee eeeeeeeeeeeee ee eee eeeeeee eee eeeeeeeeeeeee 8.88M. Meee eeeeeee eeee ee eee Meeee eeeeeee eee eeeeeee ee 8.8M eeeee eeeee, eee eeee eeeeeeee ee eeeeeee eeeeeeeee.

8,8-Meeeeeee-8-eeeeeeeee-8-eee (88, M8=Me; M8=e-Me); Meeeeee Meeeeeeee:[‌88‌]

Me e eeee ee eee eeeeeeee eeeeeeee 88 (M8=Me; M8=e-Me; 8eeee) ee MMM (8eM) eeeeee ee 8°M eee eeeee e 8.8M eeee ee eee Meeee eeeeeee 88 ee eeeeeee (8eM, 8eeee). Meeee eee eeeeeee eee eeee eeeeeee eee 88eee, Me8M (~88eM) eee eeeee, eeeeeeee ee eee eeee eeeeeeee ee 8.8M ee MeMM (88 eeeee) ee eeeeeee eee eeeeee Me eeeeeeeee. Mee eeee eee eeeeeee eee eeeee (Me8MM8), eeeeeeee eeeeeee Meeeee, eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Mee eeeee eeeeeee eee eeeeeeee ee eeeeeeeeeeeeee (eeeee eeeeeee, eeeeeee/Me8M 88:8 ee 88:8); eeeee: 88%.

(8-Meeeeeeeeeeeeeeeeee)eeeeeee (88); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meee eeeeeeeeeeeeeeeee ee eeeeee eeeeeeeeee.

Me e eeeee-eeeeee, 888-eM eeeee-eeeeeeee eeeee, eeeeeeee eeee e eeeeeeee eeeeeee eee eee ee eee eeeeeee, eeeeeee eeee Me(Me)8Me8 (88; 88.88e, 88.8eeee), eee eeeeeee eeee eeeee, eee eeeee 8.8M Me8Me ee eeeeeee (88eM, 888eeee) ee eeeeeee eeee e eeeeeeeee eeeeeeee. (Mee eeeeeeeee eeeeeeee eee eeeeeeeeee eeee eeeeeee eeee eeeee, eeeeee eeee e eeeeee eeeeee, eee eeeeeee ee eeeeeee eeee ee Meeeeee Meee/Meee eeeeee.) Mee eeeeeeeee eeee eee eeeeeee eee eeeeeee ee ee eeee eeeeeee eeeeeeeee ee MM8 eeeeeee eee eeeeeee. Meeee 88e ee eeeeeeee, eeeeeeeeee 8.8M Me8Me ee eeeeeee (88eM, 88eeee) eee eeeee ee eee eeeee eeeeee eee eeeeeeee eee eeeeeeeee eee 88e ee eeee e eeee ee eee Meeee eeeeeee 88. M 888-eM eeeee-eeeeeeee eeeee eeeeeeee eeee e eeeeeeee eeeeeee eee eee eeeeeee eeee 8-eeeeeeeeeeeeeeee-8-eee (88; 88.88e, 88.8eeee) eee eeeeeee eeee eeeee eee eeeeee eeee e eeeeee eeeeee. M eeeeee ee eeeee MMM (88eM) eee eeeee ee eeeeeee, eee eee eeeeeeeee eeee eee eeeeeee eee eeeeee ee 88°M. Mee eeeeeeeeee eeeeeeee eeee ee eee Meeee eeeeeee 88 eee eeeee eee eeeeeee eeee 88eee eeeee eee eeeeeeeee eeeeeee eee eeeeeeeeee ee ee eeeee 88°M. Meeeeeee eee eeeeeeeee eee 8.8e ee 88°M, 8.8e ee 88 ee 8°M, eee eeeeeee eee 8e ee ee. Mee eeeeeeeee eeee eee eeeeeee eee eeeeeee eeee MMM (88eM) eeeee ee eeeeeee, eeeeeeeeee eeeeeee, eee eeeeee ee 88°M. M eeeeee ee 88% ee MeMM (88eM) eee eeeee eeeeeeeee ee 8.88.8-eM eeeeeeee ee eeeeeee eeee eeeeeeee eeeeeeeee ee MM8, eeeee eee eeeeeee eee eeeeeeeeee ee 88°M ee eeeee. Meee eee eeeeeee eeeeee eee eeeeeee eee eeeeeeee eeeeeeee, eee eeeee eee eeeeeee ee eeee eeee eeeeeeee eeeeeee, eee eee eeeeeeeee ee eee MeMM eeee eee eeeee ee eeee eeeeee eeeeeeee ee eee eeee eeeee. Meeeeeeeee eeeeeeee ee ee eeeeeeee e eeeeeee eeeeeeeeee e eeee eeeeee eeeeeeeeeee eeee e eeeee eeeeee ee eeeeeeee eeeeee eeeeeeeeeee, eeeee eeeeee eeeeeeeee eeee eeeeeeee. Mee eeeeeeeeeee eeeeeee eeeeee eeeeee ee ee eeeeeeeee eeeeee eeeee, eee ee eeeeeee eeeeee eee eeeeeeee. Mee eeeeeee eee eeeeeeee eeeeeee e Meeeee eee ee e eeeeee eeee eeee eeeeeee, eee eee eeeeeeeeeee eee eee eeee eeeeeeeee eeeeee eeee eeeeeeeee eeeee Me8M. Mee eeeeeeee eeeeeeeee eee eeeeeeee eeee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeeeee e eeeee eeeeee eeee ee eeeee eeeeeee ee eeeeeee, eeeee eee eeeeeee eeee eeeeeee (888eM) ee eeeeeeeeeee e eeeee eeeeee ee eeeeee eeeee. Meeee eeeeeeeeee eeeeeee e eee ee eeeeee eee (ee e eeeeee eeee eeee eeeeeee) eeee eeeeeee eeeeeee ee eee eeeeeeeeeee eeee eeeeeee eeeee eeeeeee, eee eeeeeeee eeeeeee eee eeeeeeee eeee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeee e eeeeee eee; eeeee: 88.88e (88%). Meeeee eeeeeeeeeeee (ee 88°M/8Meee) eeeeeeee eee eeee eeeeeee ee e eeeeeeeee eee; eeeee: 8.88e (88%).