Origin of the Diastereoselection in the Indium-Mediated Addition of Haloallylic Sulfones to Aldehydes

Abstract

[reaction: see text] The R(1) substituents at C(2) of the haloallylic sulfones 1 play a pivotal role in controlling the diastereoselectivity of the indium-mediated addition reaction to benzaldehyde to produce the homoallylic alcohols 3. The R(1) Me group of 1 prefers the chair form in the In-coordinated six-membered cyclic transition state to give anti-3a, and the R(1) Ph group of 1 favors the twist boat form to give syn-3n, both in a high 13:1 selectivity.

Systematic Synthesis of Diphenyl‐Substituted Carotenoids as Molecular Wires

“…The indium‐mediated addition of chloroallylic sulfone 11a (R 2 = Ph, R 3 = H, Scheme ) to benzaldehyde produced homoallylic alcohol 22ā with high syn (OH and CH 2 SO 2 Ph) selectivity (>11:1), which underwent oxonia‐Cope rearrangement, at 80 °C in the presence of stoichiometric camphorsulfonic acid (CSA) and benzaldehyde to yield 5ā (Scheme ), as was previously reported . (2 Z ,4 E )‐Dienyl sulfone 5ā (X = H) with a phenyl substituent at C‐2 was obtained in a reasonable yield (ca.…”

Recent Advances in Indium-Promoted Organic Reactions

“…With a methyl substituent, the six-membered chair-like transition state led to the homoallylic alcohol anti-5, whereas a phenyl substituent induced a twist-boat transition state and led to syn-5. 34…”

Conductance Control in Stabilized Carotenoid Wires

“…After several years trial and errors, we finally completed the synthesis of the novel carotenoids 2 and 3 by the application of the double elimination protocol to the coupling product between the newly proposed dialdehyde 5 or 6 and two equivalents of allylic sulfone 4 ( Figure 1). [25][26][27][28] The carotenoids were purified by recrystallization and characterized to be all-trans configuration. These carotenoids were stable enough to be stored at 0 8C in the dark over a year without any decomposition.…”