Science of Synthesis

Driver, T. G., Science of Synthesis: Cross Coupling and Heck-Type Reactions, (2013) 2, 322.

More recent progress has also been achieved using azides as the metal nitrene precursor. Aryl azides ‌51‌ are used in the amination of secondary benzylic C—H bonds to afford 2-aryl-substituted indolines ‌52‌ and indoles ‌53‌ using 2 mol% of an iridium(I) catalyst at room temperature (‌Scheme 11‌).[‌61‌] The electronic constraints of this reaction are similar to the examples described above: high conversions are possible only when the starting aryl azide is substituted with a strongly electron-withdrawing group. In contrast, no such electronic constraints are observed at the benzylic site: both electron-rich and electron-deficient arenes are tolerated. In every case, the indoline product is unstable toward silica gel and purification using flash column chromatography affords a separable mixture of indoline and indole.

‌Meeeee 88‌ Meeeeee(M)-Meeeeeeee Meeeeeeee ee Meeeeeeee eeee Meee Meeeee[‌88‌]

‌Meeeeeeeeee 88‌

e Meeeeeee eeeee eeeee eeeeee eeeeeeeeeeeeee (eeeeee eee).

Me eeeeeeee ee eeeee eeee eeeeee, eeeeeeeeeeeeee M—M eeee eeeeeeeee eee ee eeeeeeee eeeee eeeeeeeeeeeee eeeeee ‌88‌ ee eeeeee e eeeeeee ee eeeeeeeeeeee ‌88‌ (‌Meeee 88‌).[‌88‌] Meeeee eeeeeeeeeeeeeeeeeeee (8 eee%) ee eee eeeeeee eeeeeeee ee eeeeeee eeeeeeee-eeee eeeeeeee. Mee eeeeeeee eeeeeeeee e eeeee ee eeeeeeeeee eeeeee eeeeeeeee eeeee- eee eeeee eeeeee, eee eeeeeeee-, eeeeeeeee-, eee eeee eeeeeee M—M eeeee eee ee eeeeeeeeeeeeee. Meeeeeeeeeeee, eee eeeeeeeeee ee eeeee eeeee eeeeee ee ee eeeeeeee > eeeeeeeee > eeeeeee.

‌Meeee 88‌ Meeeee(MM)-Meeeeeeee Meeeeeeee ee Meeeeeeeeeee eeee Meeeeeeeeeeee Meeeee[‌88‌]

Meeee	Meeeeeeee	Meeeeee	Meeeee (%)	Mee
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]

e Meeeeeee eeeee eeeee eeeeeeeeeeeeee (eeeeee eee).

Meeeeeeeee eeeeee ‌88‌ eee eeee eeeeee eeeeeeeeee ee eeeee eeeeeeee (‌Meeee 88‌).[‌88‌] Mee eeee eeeeeeee-eeee-eeeeeeee eeeeeeee, eeeeee eeeeeeeeeeeeeeeeeeee ee eeeeeeee ee e eeeeeeee. Meeeeee, 8 eee% ee eee 8,88-eee[8,8-eee(8-eeeeeeeeeeeeeeeee)eeeeee]-88,88-eee(8,8-ee-eeee-eeeeeeeeeee)eeeeeeeee-eeeeeee eeeeee eeeeeeee [Me(eee)] eeeeeeeeeee eeeeeeee eee eeeeeeeee ee e eeeee ee eeeeeeeeeeeeeeeeeeeee. Meee eeeeeeee eeeeeee eee eeeeeeee eeee eeeeeeeeeee eee eeeee eeeeeee eeeeeeeee eeeeeeeeeeee eee eeeeeeee eeeeeee.[‌88‌,‌88‌] Meeee eeee eeeeeeee, e eeeee ee eee- eee eeeee-eeeeeeee eeeeeeeeeeeeeeee ‌88‌ eee ‌88‌, eeeeeeeeeeee, eee ee eeeeeeee, eeee eee-eeeeeeee eeee eeeeeeeee eeeee eeeeeee eee eeeeeeeeee eeeee eeee eeeeeeee eee eeeeeeee.

‌Meeee 88‌ Meeeee(MM)-Meeeeeeee Meeeeeeee ee Meeeeeeeeeeeeeeeeeeee eeee Meeeeeeeee Meeeee[‌88‌]

Meeee	Meeeeeeee	Meeeeee	Meeeee (%)	Mee
8			88	[‌88‌]
8			88	[‌88‌]
8			88e	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]

e Meeeeeee eeeee eeeee eeeeee eeeeeeeeeeeeee (eeeeee eee).

e ee 88:88.

Meeeeeeeeeeeee M—M eeee eeeeeeeee eee eeee ee eeeeeeeee ee eeeeee eeeeeeeee eeeeeeeee ee eeeeeeeeeee eeeeeeeeeeeee eee eeeeeeee eeeeeeee (‌Meeee 88‌).[‌88‌] Meeeeee ee eeeee eeeeeeee eeeeeee,[‌88‌,‌88‌] eeeeeeeeeeee eee eeeeeeee eeee e 8,8,8-eeeeeeeeeeeeeeeeeeeeeee eeeee eeeeeee eee eeeeeee eeeeee eee eeeeeeeeeeee eee eeeeeeee-eeee eeeeeeee. Meeee 8,8,8-eeeeeeeeeeeeeeeeeeeeeee eeeee (‌88‌), eeeeeeeeeeee eeeeeeeee eeeeee eeeeeeeeeeeeeeeeeeee eeeeeeeee eee eeeeeeeee eeeeeeeeeeeeeeeee ee e eeeee ee eeeee-eeeeeeeeeee eeeeee ee eee eeeeeeee eeeeeeee ee eeee (8,8,8-eeeeeeeeeeeeeeeeeeeeeee)eeeeee ‌88‌. Mee eeeee, eeeeeee, ee eeeeeeeeee ee ee eeeeeeeeee eeeee eeeee eeeeeeeeeee.

‌Meeee 88‌ Meeeee(MM)-Meeeeeeee Meeeeeeeeeeeee Meeeeeee M—M Meee Meeeeeeee[‌88‌]

Meeee	Meeeeeeee	Meeeeee	Meeeee (%)	Mee
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]
8			88	[‌88‌]

e Meeeeeee eeeee eeeee eeeeee eeeeeeeeeeeeee (eeeeee eee).

Meeeeeeeeeee Meeeeeeee

8-Meeeee-8-eeeeee-8,8-eeeeeee-8M-eeeeee (‌88‌, M8 = M; M8 = M; Me8 = Me) eee 8-Meeeee-8-eeeeee-8M-eeeeee (‌88‌, M8 = M; M8 = M; Me8 = Me); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meeeee eee ee eeeee eeeeeeeee. Me eee M/M eeeeee (<8:8), eeeeee eee eeeeeeee eeee eeeeeeeeeeeee ee ee eeee eeeeeeeeeeee.

Me e eeeeeee ee eeee eeeee ‌88‌ (M8 = M; M8 = M; Me8 = Me; 888 ee, 8.888 eeee) eee {Me(MMe)(eee)}8 (8 ee, 8 eee%) eee eeeee eeeeeee (8.8 eM) (MMMMMMM: eeeeeeeeee). Mee eeeeeeeee eeeeeee eee eeeeeee ee 88 °M eee 88 e. Mee eeeeeeeeeeeee eeeeeee eee eeeeeeee eeeeeee Meeeee, eee eee eeeeeee eee eeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeeeee eeeeeee eee eeeeeeee ee MMMM (eeeeee eee, MeMMe/eeeeeee 8:888 ee 8:888); eeeee ee 8-eeeeee-8-eeeeee-8,8-eeeeeee-8M-eeeeee (‌88‌, M8 = M; M8 = M; Me8 = Me): 88 ee (88%); eeeee ee 8-eeeeee-8-eeeeee-8M-eeeeee (‌88‌, M8 = M; M8 = M; Me8 = Me): 88 ee (88%).

8,8-Meeeeeee-8,8-eeeeeeeeeee-8,8-eeeeeee-8,8-eeeeeeeeeeeee 8,8-Meeeeee (‌Meeee 88‌, Meeee 8); Meeeeee Meeeeeeee:[‌88‌]

Me eeee-eeeee Meeeeee eeee eee eeeeeee eeee 8,8,8-eeeeeeeeeeeeeeeeeee-8-eeeeeeee eeeee (8.8 eeee), eeeeee eeeeeeeeeeeeeeeeeeee (8 µeee), eee 8-Å eeeeeeeee eeeeee (888 ee). Mee Meeeeee eeee eee eeeeeeeee eee eeeeeeee eeee M8. Mee Meeeee eeeee eee eee eeeeeeee eeee e eeeeee eeeeee eee eeeeeeeeeeeee (8.8 eM) eee eeeee. Mee eeee eee eeee eeeeee eeee M8 eee 8 eee, eee eee eeeeee eeeeee eee eeeeeeee eee eeee eeeeee eeee e Meeeee eeeee eee. Mee eeeeeeeee eeeeeee eee eeeeee ee 88 °M. Meeee 88 e, eee eeeeeee eee eeeeee ee eeeeeee eeeeeeeeeee eee eee eeeeeee eee eeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeee eee eeeeeeee ee e Meeeeeee eeeee eeeeeeeeeeeeee eeeeeeeeee (MeMMe/eeeeeee 8:888 ee 88:88) ee eeeeee eee eeeeeee ee e eee eeeee; eeeee: 88.8 ee (88%).

8-(8,8-Meeeeeeeeeeeeee)-8-eeeeee-8,8-eeeeeee-8M-8,8,8-eeeeeeeeeeeeeeeeeeee 8-Meeee (‌Meeee 88‌, Meeee 8); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meeeee eee ee eeeee eeeeeeeee. Me eee M/M eeeeee (<8:8), eeeeee eee eeeeeeee eeee eeeeeeeeeeeee ee ee eeee eeeeeeeeeeee.

Me eeee-eeeee Meeeeee eeee eee eeeeeee eeee eee eeeeee eeeeeeeee Me(eee) (8 µeee) eee 8-Å eeeeeeeee eeeeee (888 ee). Mee Meeeee eeee eee eeeeeeeee eee eeeeeeee eeee M8. Mee Meeeee eeeee eee eee eeeeeeee eeee e eeeeee eeeeee eee (eeeeeeeeeeeeeee)eeeeeee (8.8 eM), eee(8,8-eeeeeeeeeeeeee) eeeeeeeeeeeeeee (8.8 eeee), eee (eeeeeeeeeeeeeee)eeeeeee (8.8 eM) eeee eeeeeeeeeeee eeeee. Mee Meeeeee eeee eee eeeeee eeee M8 eee 8 eee eee eee eeeeee eee eeee eeeeeeee eeee e Meeeee eeeee eee. Mee eeeeeee eee eeeeee ee 88 °M. Meeee 88 e, eee eeeeeee eee eeeeee ee eeeeeee eeeeeeeeeee eee eee eeeeeee eee eeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeee eee eeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, MeMMe/eeeeeee 8:8) ee eeeeee eee eeeeeee ee e eeeee eeeee; eeeee: 88%.

8,8,8-Meeeeeeeeeeeee 8,8,8,8-Meeeeeeeeeeeeeeeeeee-8-eeeeeeeeeee (‌Meeee 88‌, Meeee 8); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meeeee eee ee eeeee eeeeeeeee. Me eee M/M eeeeee (<8:8), eeeeee eee eeeeeeee eeee eeeeeeeeeeeee ee ee eeee eeeeeeeeeeee.

M Meeeeee eeee eeeeeeeeee 8-Å eeeeeeeee eeeeee (888 ee) eee eeeeee ee ee eeee. Meeee 88 e, eee eeee eee eeeeee ee eeeeeee eeeeeeeeeee, eee eeeeee eeeeeeeeeeeeeeeeeeee (8.88 eeee) eee eeeee. Mee eeeeeee eee eeeeeeeee eee eeeeeeeeee eeee M8. Mee Meeeee eeeee eee eee eeeeeeee eeee e eeeeee eeeeee eee 8,8,8-eeeeeeeeeeeeeeeeeeeeeee eeeee (‌88‌; 8.8 eeee) eee eeeee eeeeeeee ee 8,8,8,8-eeeeeeeeeeeeeeeeeeeee (88 eeeee). Meeee eee eeeeeee eee eeeeee eeee M8 eee 8 eee, eee eeeeee eeeeee eee eeeeeeee eeee eee Meeeee eeeee eee. Mee eeeeeee eee eeeeee ee 88 °M. Meeee 88 e, eee eeeeeee eee eeeeee ee eeeeeee eeeeeeeeeee eee eeeeeeee eeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee); eeeee: 8.88 eeee (88%).

References