Science of Synthesis

Perkins, M. V., Science of Synthesis, (2008) 36, 688.

The reactions of allylstannanes with aldehydes generally occur under one of three conditions: thermally induced, Lewis acid catalyzed, or via transmetalation. Of these, Lewis acid catalyzed reactions are the most important and commonly observed. Transmetalation reactions are covered within sections that deal with the appropriate converted metal. An early example[‌53‌] of a thermal addition of a crotylstannane is shown in ‌Scheme 30‌. In this case the addition of (Z)-tributyl(crotyl)stannane (Z)-‌66‌ to trichloroacetaldehyde gives the product ‌68‌ in very high diastereoselectivity. This selectivity can be rationalized by consideration of a cyclic transition structure ‌67‌. On the other hand, the reaction of the (E)-tributyl(crotyl)stannane (E)-‌66‌ to benzaldehyde gives predominately the anti-product ‌69‌,[‌54‌,‌55‌] presumably via an analogous transition state. The high temperatures required for these reactions often lead to low yields and, as a result, the thermal versions are little used.

‌Meeeee 88‌ Meeeeee ee Meee-Meeeeeee Meeeeeeee ee (M)- eee (M)-Meeeeeeeeeeeeee eeee Meeeeeeee[‌88‌–‌88‌]

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‌Meeeee 88‌ Meeeeeeee ee (M)- eee (M)-Meeeeeee(eeeeee)eeeeeeeee eeee Meeeeeeeeeeeeeeeeeeeeee[‌88‌]

‌Meeeeeeeeee 88‌

Mee eeeeeeeeeeeeee eeeeeee ee eeeee eeeeeeeee ee eeeeeeeeeeee ee e eeeeeeeeee eee eeeeeeeeeeeeee eeeeeeeeee eeeeee ‌88M‌ [eee eeee eee (M)- eee (M)-eeeeee eeeeeee], eeeee eeeee eee eeeeeee ‌88M‌, eeeeee eeee eee eeee eeeeee, eeeeeeeee eeeeeeeeeeeeee ‌88M‌ ee eeeeeeeee eeeeeeeeee eeeeee ‌88M‌ eeee eeeeee ee eee eeeee eeeeeee ‌88M‌ (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeeee Meeeeeeeee Meeeee eee eee Meeee Meee Meeeeeeee Meeeeeeee ee Meeeeeeeeeeeeee ee Meeeeeeee

M eee eeeee ee eeeeeeeee(eeeeeeeeeeeeeee)eeeeeeee eeeeeeee ‌88‌ eee eeee eeeeeeee. Meeee “eeeeeeee” eeeeeeee eeeee eeeeeee eeeeeeeee eeeeeeeeee eee eeeeeeee ‌88‌ eee eee eeeeeeee eee eeeeeee[‌88‌] ee Meeee eeee[‌88‌,‌88‌] eeeeeeee eeeeeeeee ee eeeeeeeee (‌Meeeee 88‌).[‌88‌]

‌Meeeee 88‌ Meeeeeeee ee “Meeeeeee” Meeeeeeeeeeeee eeee Meeeeeeee.[‌88‌]

‌Meeeeeeeeee 88‌

Meeeeeeeeeee Meeeeeeee

8-Meeeeeeeee-8-eeeeeeeee-8-ee-8-ee (‌88‌); Meeeeee Meeeeeeee:[‌88‌]

MM8•MMe8 (88 ee, 88 μM, 8.888 eeee) eee eeeee eeeeeeee ee e eeeeeeee eeee ee MeMMM (88 ee, 88 μM, 8.888 eeee) ee MM8Me8 (8.8 eM) eeee ee −88°M. Mee eeeeeeeee eeee eeeeee eeeeeeee eeeeee ee eeeee eee eeeeeeee eeeee; ee eee eeeeeee ee eeee eee 88 eee, eeeee eeeee (M)- ee (M)-eeeeeeee(eeeeee)eeeeeeee (888 ee, 8.888 eeee) eee eeeee eeee eee eeee ee eee eeeee ee eeeeeee eee eeeee eeeeeee. Mee eeeee ee eee eeeeeee eeeee eeeeeeee ee eeeeee e eeeee, eeee eeee eeeeee eeee. Mee eeeeeeee eee eeeeee ee ee eeeeeeee eeeee 8 e eee eee eeeeeeee eeee eeee eee. ee MeMMM8 (8 eM) ee eee eeeee eee eeeeeee eeee eee eeeeeee eeee. Meeee eeeee eeeeeee ee eeee ee ee, eee eeeeeee eee eeeeeeeee eeee MM8Me8 (8 × 88 eM), eee eee eeeeeeee eeeeeeee eeee eeeee (Me8MM8), eee eeeeeeee eeeeeee e eeee ee Meeeee (8.8 ee)/eeeeee eee (8 ee). Mee eeeeeee eee eeee eeeeeeeeee eeee eee eeeeeeee eeeee eeeeeee eeeeeeee ee eeee eee eeeee eeeee eeeeeeee ee e eeeee, eeeeeeeee eeeeee.

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) M 88e, 8888.