Science of Synthesis

Kempa, S.; Wallach, L.; Rück-Braun, K., Science of Synthesis, (2010) 41, 487.

In 1986 the reactions of the lithium salts of tert-butylhydrazones ‌63‌ with electrophiles were reported. The electrophiles (E+) applied in these investigations were aldehydes, ketones, alkyl halides, and (2E)-but-2-enoates (crotonates).[‌147‌] tert-Butylhydrazones react with alkyllithium compounds or lithium diisopropylamide in tetrahydrofuran at 0°C to give the ambident azo-stabilized nucleophilic anions ‌64‌. These intermediates can react with the electrophiles either on nitrogen or at the carbon atom as shown in ‌Scheme 41‌. Diazene anions derived from methylhydrazones or phenylhydrazones react with alkyl halides principally on nitrogen. In the case of tert-butylhydrazones it is found that the steric effect of the bulky tert-butyl group directs the reaction along the desired C-addition pathway for most electrophiles.[‌147‌]

‌Meeeee 88‌ Meeeeeeee ee eee Meeeeee Meeee ee eeee-Meeeeeeeeeeeeee eee Meeee Meeeeeeeee eeeeee Meeeeeeeeeeee[‌888‌]

Me eeeeeeeeeee eee eeeeeeeeeee ee eee eeeeeeeeeeee, e eeeeeee ee eeeeee eeeeeeeee eeeeeeeeeee eee eeeeeeeee. Me e eeee eeeeee ee ee eeeeeeee ee eeeeeee eeeeeeeee eeee eeeeeee.[‌888‌] Mee eeeeeee eeee eee eeeee eeeeeee ee eeeeeeeee eeeeeeee ee eeeee ee eee eeeeeeee ee eeee-eeeeeeeeeeeeee ‌88‌ eeee eeeee eeeeeeee (‌Meeeee 88‌).[‌888‌] Meee, eee eeeeeee eeee ee eee eeee-eeeeeeeeeeeeee ‌88‌ ee eeeeee ee eeee ee eeeeeeee ee e 8.8 M eeeeeeee ee eeeeeeeeeeeee ee −88°M. Mee eeeeeee ee eeeeee ee eee eeeeeeee eeeeeeeeeee ee −88°M eeeeee eee eeeeeeee ee eeeee eeeeeeee ee eeeeeeeeeeeeeee ee eeeee. Meeee eeeeeeeeee eeeee 88% ee eee eeeeeee eeeee 8-(eeee-eeeeeeeeeeeee)-8-eeeeeeeeeeeeeeee (‌88‌).

‌Meeeee 88‌ Meeeeeee ee e Meeeeeeee eeee-Meeeeeeeeeeeee eeee Meeee Meeeeeee[‌888‌]

Meee eeee-eeeeeeeeeeeeee ‌88‌ ee eeeeeee eeeee eeeeeee eeeeeeee eeeeeeeeee eeee 8,8-eeeeeee- ee 8,8-eeeeeeeeeeeee eee eeeee eeeeeee ee e 8,8-eee(eeeeeeeeeeeee)eeeeeee.[‌888‌] Me eee eeeeeeee ee M,M,M′,M′-eeeeeeeeeeeeeeeeeeeeeeeeee eeeeee eeeeee eee eeeeeeee ee eeeeeeeee eeee eeeeeeeeeeee eeee-eeeeeeeeeeeeee eee eeee ee eeeeeeeee eeee 8-eeeeee-8-eeeeeeeeeee ee eeeeeeeeeeee.[‌888‌] ‌Meeeee 88‌ eeeee ee eeeeeeee ee eeeeeeeee ee eeee-eeeeeeeeeeeeeee ‌88‌ eeee eeeee eeeeeee ee eeee eeee-eeeeeeeeeeeee ‌88‌. Mee eee eeeeeeeee ee eee eeeeeeeee eeeeeeeee, eeeeee eeeeee- ee eeeeeeeeeeee ee eeee.

‌Meeeee 88‌ Meeeeeeeee ee Meeeeeeee eeee-Meeeeeeeeeeeeee eeee Meeee Meeeeee[‌8‌,‌888‌]

‌Meeeeeeeeee 88‌

M8	M8	M	Meeeeeeeee	Meeee (%)	Mee
Me	(MM8)8Mee	M	8.8 M MeMe (8.88 eeeee), MMMM (8 eeeee), MMM, −88 °M ee ee, 8 e	88	[‌8‌]
Me		Me	88.8 M MeMe (8.8 eeeee), eeeeee, MMM, 8–88°M, 88 e	88	[‌888‌]
Me		Me	88.8 M MeMe (8.8 eeeee), eeeeee, MMM, 8–88°M, 88 e	88	[‌888‌]
M		Me	8.8 M MeMe (8.88 eeeee), MMMMM (8.88 eeeee), MMM, −88 ee 88°M, 8 e	88	[‌888‌]
M	Me	Me	8.8 M MeMe (8.88 eeeee), MMMMM (8.88 eeeee), MMM, −88 ee 8°M, 8 e	88	[‌888‌]
M	MM8MM=MMMe	M	8.8 M MeMe (8.8 eeeee), MMM, −88 ee 8°M, 8 e	88	[‌888‌]
Me	MM8MM=MM8	Me	88.8 M MeMe (8.8 eeeee), eeeeee, MMM, 8–88°M, 88 e	88	[‌888‌]
M	MM8MM=MM8	Me	8.8 M MeMe (8.88 eeeee), MMMMM (8.88 eeeee), MMM, −88 ee 88°M, 8.8 e	88	[‌888‌]
M	(MM8)8Me	M	8.8 M MeMe (8.88 eeeee), MMMMM (8.88 eeeee), MMM, −88 ee 8°M, 8 e	88	[‌888‌]
M	Me	M	8.8 M MeMe (8.88 eeeee), MMMMM (8.88 eeeee), MMM, −88 ee 88°M, 8 e	88	[‌888‌]

M eeeeeee eeeeeee ee eeee eeeeeeee eeee ee eee eeeeeeeee eeee-eeeeeeee eeeeeeee eeeeeeeee ee 8-(eeee-eeeeeeeeeeeee)-8-(8,8-eeeeeeeee-8-eeeeeee)eeeeee-8-eee (‌88‌, e = 8) eee 8-(eeee-eeeeeeeeeeeee)-8-(8,8-eeeeeee-8-eeeeeee)eeeeee-8-eee (‌88‌, e = 8), eeeee eee eeee ee eeeeeee eee eeeeeeeeeeeeeeeeee(8).[‌888‌] Mee eeeeee eeeeeeeee ee eeee-eeeeeeeeeeeeee ‌88‌ eeee eeeeee eeeeeeeee eee eee eeeeeeeeeeeee α,ω-eeeeeeeeeeeee eeee eee eeeeeeee ee eeeeeeee eeeeee (‌Meeeee 88‌).

‌Meeeee 88‌ eeee-Meeeeeee Meeeeeee Meeeeeeee ee 8-(eeee-Meeeeeeeeeeee)-8-(8,8-eeeeeeeee-8-eeeeeee)eeeeee-8-eee eee 8-(eeee-Meeeeeeeeeeee)-8-(8,8-eeeeeee-8-eeeeeee)eeeeee-8-eee[‌888‌]

Me eeeeeee eeeeeee, 8-eeeee-8-(8-eeee-8,8,8-eeeeeeeeeeeee-8-eeee)eeeeeeee ‌88‌ eee eeeeeeee eeee 8-eeeee-8-(eeeeeeeeeeeee)-8-eeeeeeeeeeeeeeee ‌88‌ eeee eeeeeeeeeeeeeee eeeeeeeee ee eee eeeeeeee ee eeeeeeee (‌Meeeee 88‌).[‌888‌,‌888‌] Me e eee-eeee eeeeeee, eee eeeeeeeeee ‌88‌ eee eeeee eeeeeee eeee 8 eeeeeeeeeee ee eeeeeeeeeeeeeee eeeeeeeee eee eeeeeeee ee eeee eee eee eeeeeeeeee ‌88‌. Meeeeeeee ‌88‌ eeeee eeeeeee ee eee eeeeeeee ee e eeeeeee 88 eeeeeeeeeee ee eeeeeeeeeeeeeee eeeeeeeee ee eeeeeeee ee eeee eee eeeeeeee ‌88‌. Mee eeeeee eeeeeee eeee 88 eeeeeeeeeee ee eeeeeeeeeeeeeee eeeeeeeee eee 88 eeeeeeeeeee ee eeeeeeee, eeeeeeeeee eee eeeeeeee ‌88‌ ee eeeeee eeee 8 ee 88%.

‌Meeeee 88‌ Meeeeeeee ee Meeeeeeeee eeee Meeeeeeeeeeeeee Meeeeeeee ee eee Meeeeeee ee Meeeeeee[‌888‌,‌888‌]

‌Meeeeeeeeee 88M‌

e Meeee eeeeeee ee eeee eeeeeeee eee 8-eeee-eeeee-8-(8-eeeee)-8-(eeeeeeeeeeeeeee)eeeeeeee (88%).

e 8-Meeeee-8-eeee-eeeee-8-(eeeeeeeeeeeeeee)eeeeeeee eee eeeeeeee ee e eeeee eeeeeee (88%).

‌Meeeeeeeeee 88M‌

e e.e. = eee eeeeeeee.

Meeeeeeeeeee Meeeeeeee

8-[8-(8-Meeeeeeeeee)eeeee]-8-eeee-eeeeeeeeeeee (‌88‌, M8 = M; M8 = 8-MeM8M8MM8); Meeeeee Meeeeeeee:[‌888‌]

MMM (8 eM) eee eeeeee ee −88 ee −88°M. 8-eeee-Meeee-8-eeeeeeeeeeeeeeeeee (‌88‌, M8 = M; 8.88 e, 88.8 eeee), 8.8 M MeMe (8 eM, 88.8 eeee), eee MMMMM (8.8 eM, 8.8 eeee) eeee eeeee eeeeeeeeeeeee eee eee eeeeeee eee eeee eeeee M8 ee −88 ee −88°M eee 88 eee, eeeeee eee eeeeeeeeeee eee eeeeeee ee eeee ee −8°M. 8-Meeee-8-(eeeeeeeeeee)eeeeeee (8.88 e, 88.8 eeee) eee eeee eeeee eeee 8 eee. Meeee eee eeeeeeee eee eeeeeeee, eee eeeeeee eee eeee ee 8–88°M eee 8 e. Mee eeeeeeeee eeeeee eee eeee eeeeeeeee eeee eee ee MMe eee eeeeeeeee eeee Me8M. Mee eeeeeeee eeeeeee eeeeeeee eeee eeeeee eeee eee ee M8MM8 eee M8M. Meeee eeeeee (MeMM8), eee eeeeeee eee eeeeeeeeee ee eeee eee eeeeeee; eeeee: 8.8 e (88%). Mee eeeeeee eeeeeeeee e eeeee eeeeeeee, eeeee eee eeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, Me8M/eeeeeeeee eeeee 8.8:88.8) ee eeeeee eee eeee eeeeeee ee ee eee.

8-Meeeee-8-[8,8,8-eeeeeeeee-8-(8-eeeeeeeeeeeee)eeee-8-eeee]eeeeeee (‌88‌, M8 = 8-MeMM8M8; M8 = Me); Meeeeee Meeeeeeee:[‌888‌]

Meeeeeeeeeeeeee eeeeeeeee (8.8 eM, 88 eeee) eee eeeee ee ee eee-eeee eeee ee 8-(8-eeeeeeeeeeeeeeeeee)-8,8-eeeeeeeeeeeeeeeee (‌88‌, M8 = 8-MeMM8M8; M8 = Me; 888 ee, 8.8 eeee) ee eee eeeeeeee (8 eM). Meeee eeeeeeee ee ee eee 88 e, eee eeeeeee eee eeeeeeeeee eeeee eeeeeee eeeeeeee eee MM8Me8 (88 eM) eee eeeee ee eee eeeeeee. Mee eeeeeeeee eeeeeee eee eeeeee eeee 8.8 M MMe (888 eM), M8M (888 eM), eee ee Me8MM8 (888 eM). Meeee eeeeee (MeMM8), eee eeeeeee eee eeeeeeeeee eeeee eeeeeee eeeeeeee eee eee eeeeeee eee eeeeeeee ee Meeeeeeee eeeeeeeeeeee; eeeee: 888 ee (88%).

References