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40.1.1.3.2.2.2.2 Variation 2: Of Organozinc Reagents

DOI: 10.1055/sos-SD-040-00206

Friestad, G. K.Science of Synthesis, (200940327.

The addition of dialkylzinc reagents to imines and related compounds offers the possibility of asymmetric induction through the use of Lewis basic and Lewis acidic additives. The organozinc reagents are less reactive than the corresponding organolithium or Grignard reagents, so the additive can accelerate the reaction and racemic background reactions can be avoided. Examples of both types are provided below.

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Meeee M8 M8 M Meeeeeeee ee (%) Meeee (%) Mee
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8 8-MeM8M8 Me M(M)Me8 88 (8 eeeee) 88 88 [‌888‌]
8 Me Me M(M)Me8 88 (8 eeeee) 88 88 [‌888‌]
8 8-MeMM8M8 Me M(M)Me8 88 (8 eeeee) 88 88 [‌888‌]
8 Me Me M(M)Me8 88 (8 eeeee) 88 88 [‌888‌]
8 Me Me Me Me(MMe)8, 88 (8eee%) 88 88 [‌888‌,‌888‌]
8 8-MeMM8M8 Me Me Me(MMe)8, 88 (8eee%) 88 88 [‌888‌,‌888‌]
8 Me Me Me Me(MMe)8, 88 (8eee%) 88 88 [‌888‌,‌888‌]
88 (MM8)8Me Me Me Me(MMe)8, 88 (8eee%) 88 88 [‌888‌,‌888‌]
88 Me Me M(M)Me8 Me(MMe)8, 888 (8eee%) 88 88 [‌888‌]
88 8-MeMM8M8 Me M(M)Me8 Me(MMe)8, 888 (8eee%) 88 88 [‌888‌]
88 8-eeeee Me M(M)Me8 Me(MMe)8, 888 (8eee%) 88 88 [‌888‌]
88 eeeeeeeeeee Me M(M)Me8 Me(MMe)8, 888 (8eee%) 88 88 [‌888‌]
88 Me Me M(M)Me8 Me(MMe)8, 888 (8eee%) 88 88 [‌888‌]

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Mee eeeeeeeeeee ee eeeeeeeeee eeeeeeeeeeeeeeee ee eeeeeeeeeeee eeee eeeeeeee 8-eeeeeeeeeeeeeeeeeeee eeeeeee 888 (Meeeee 88), eeeee eee eeeeeeeee eeee eee eeeeeeeeeeeee eeeeee ee eeee.[‌888‌] Mee eeeeeeeeeee, eeeeeee eeeeeeeeee eeeeeeeee eeee eeeeeeeeeee eeeeeeeeeeeee eee eee eeeee eeeeeeee eeeeeeee, eeeeee 888, eeee eee (M,M)-MeeMMMM (888)eeeeee(MM) eeeeeeeeeeeeeeeeeeeeeeeee eeeeeeeee eeeeee ee eeee (Meeeee 88). Meeeeeeee eeeeeee eee eeee ee eeeeeee eeee eeeeeeeeeeeeee eeeeeeeeeee, eeeeeee ee e eeeeeeeee ee eeeeeeeeeeee ee 88% ee.[‌888‌] Me eeeeeeeee eee-eee eeeeeeeeee eee eeee eeee eeeeeeee; eee eeeeeeeeeee ee eeeeeeeeeeeeeeeeee eeeee, eeeeeeeee, eee eeeeeeeeeeee (8:8:8) ee eee eeeeeeee ee e eeeeee eeeeeeee eeeeeeee eeee eeeeee 888 eeeee eee eeeee eeeeeeee ee 8888% eeeeee eee eeeeeeeee eeeeeeeeeeeeeeeeeeee.[‌888‌] Meeee eeeeeee eeeee ee eeeeeeeeee ee eeeee eee eeeeeeeeeee eee eeeeeeeeeeeeeeee eeeeeeeeee eeeeeeeee ee eeeeee.

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Meeeeeeeeeee Meeeeeeee

M-Meeee-M,M-eeeeeeeeeeeeeeeeee Meeeee 888; Meeeeee Meeeeeeee:[‌888‌,‌888‌]

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References


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