Ozonolysis of Morita–Baylis–Hillman adducts originated from aromatic aldehydes: an expeditious diastereoselective approach for the preparation of α,β-dihydroxy-esters

Recent Contributions from the Baylis−Hillman Reaction to Organic Chemistry

“…Coelho and co-workers 718 have transformed via ozonolysis the Baylis-Hillman and TBS-protected Baylis-Hillman alcohols into R-keto carbonyl compounds, which were further reduced with NaBH 3 CN into diol derivatives. In the case of unprotected Baylis-Hillman alcohols, anti diols were obtained as major products, while protected Baylis-Hillman alcohols did not show any significant selectivity.…”

Development of the Applications of Palladium on Charcoal in Organic Synthesis

“…The Baylis–Hillman reaction has been widely utilized for carbon‐carbon bond formation, and Baylis–Hillman adducts often have been found as synthetic intermediates, heterocyclic compounds, and natural products . In 1998, the first examples of Heck reactions of Baylis–Hillman adducts were reported by three independent groups .…”

Employing Small Polyfunctionalized Molecules for a Diastereoselective Synthesis of Highly Substituted Indolines

“…We began our studies by preparing MBH adducts 9 – 15 by using an optimized experimental protocol previously reported by our group . Thus, a set of commercial aldehydes were treated with methyl or ethyl acrylate (3 equiv.)…”

“…On the basis of previous results, 9 was transformed into key intermediate 20 , which in turn could be used for the synthesis of an indoline. Thus, by using a straightforward sequence, the secondary hydroxyl group of adduct 9 was silylated to give the corresponding silyl ether 16 in excellent yield . The ozonolysis of 16 at –78 °C for 15 min followed by a reductive workup with dimethyl sulfide afforded α ‐ketoester 17 , which was not isolated but treated in situ with hydroxylamine hydrochloride in the presence of pyridine at 60 °C for 2 h to give the corresponding hydroxyiminoester 18 in good yield.…”