Sodium Hypochlorite Pentahydrate as a Reagent for the Cleavage of trans-Cyclic Glycols

Abstract

Sodium hypochlorite pentahydrate (NaOCl•5H 2 O) can be used toward the efficient glycol cleavage of trans-cyclic glycols, which are generally resistant to this transformation. Interestingly, the reaction of cis-cyclic glycols with NaOCl•5H 2 O is slower than that observed for the corresponding transisomer. This trans selectivity is in sharp contrast to traditional oxidants used for glycol cleavage. Acyclic glycols can also react efficiently with NaOCl•5H 2 O to form their corresponding carbonyl compounds in high yield.

Designed whole-cell-catalysis-assisted synthesis of 9,11-secosterols

“…Using an even longer reaction time and stoichiometric amount of the reagent, diol 5 was not oxidized to the corresponding dicarbonyl com- pound 8. However, using NaOCl•5H 2 O as an oxidant [31], diols 5 and 6 were effectively converted to the corresponding 9,11secosterols 8 and 9 within one hour at 0 °C (Scheme 3). Compound 8 was isolated as 2:1 mixture together with starting diol 5 and purified further by preparative TLC.…”

“…The general procedure of Kirihara et al [31] was followed. Sodium hypochlorite pentahydrate (3 equiv) was added to a stirred solution of diol (1 equiv) and tetrabutylammonium hydrogen sulfate (0.1 equiv) in dichloromethane (8 mL/mmol diol) and water (2.7 mL/mmol diol) at 0 °C.…”

A Concise Synthesis of 24,25-Dihydro-6-epi-Monanchosterol A

“…However, while this method allowed the regioselective oxidation of the Δ 5 -double bond in a highly efficient manner, the resulting trans-glycol (trans-5) proved recalcitrant to the planned oxidative cleavage, for instance, with NaIO 4 or Pb(OAc) 4 . Even under Kirihara's conditions (NaOCl, Bu 4 NHSO 4 ), 12 specifically designed for the cleavage of cyclic trans-glycols, the desired 5,6-secosterol (4) could not be obtained from this particular (Δ 7,8 -unsaturated) substrate. We therefore decided to prepare the corresponding cisdihydroxylated compound cis-5, which we expected to undergo the Criegee oxidation rather voluntarily (Scheme 3).…”

Nanocellulose Production via One-Pot Formation of C2 and C3 Carboxylate Groups Using Highly Concentrated NaClO Aqueous Solution

“…14 NaClO•5H 2 O is an efficient oxidant for the oxidative cleavage of glycols. 15 All these aspects are of substantial advantage for developing a one-step process for the chemical modification of the surface of cellulose microfibrils. Moreover, the reaction does not need a reagent recovery system when applied into industrial processes, which is more advantageous compared with TEMPO-mediated oxidation; special eluent treatments are necessary to remove Br ions and TEMPO-related compounds from wastewater in the TEMPO oxidation process.…”

“…In addition, an aqueous solution can be prepared with a higher concentration of NaClO than that in commercially available solutions by dissolving these crystals in water . NaClO·5H 2 O is an efficient oxidant for the oxidative cleavage of glycols . All these aspects are of substantial advantage for developing a one-step process for the chemical modification of the surface of cellulose microfibrils.…”