NaHSO4-SiO2 as an efficient and chemoselective catalyst, for the synthesis of acylal from aldehydes under, solvent-free conditions

Ravi Kumar Kannasani,Srinivasa Reddy Battula,V V Satyanarayana Peruri

doi:10.1186/1752-153x-6-136

Ravi Kumar Kannasani, Srinivasa Reddy Battula + Show 1 more

Open Access

https://doi.org/10.1186/1752-153x-6-136

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Abstract

BackgroundStructurally diverse aldehydes are successfully converted into acylals (1,1-diacetates) with acetic anhydride using NaHSO4-SiO2 as a mild, convenient and inexpensive catalyst under solvent-free conditions. The noteworthy features of the present system are shorter reaction times, and mild and solvent-free conditions. Furthermore, it offers chemoselective protection of aldehydes.ResultsBoth aromatic and aliphatic aldehydes reacts smoothly with acetic anhydride in presence of silica supported sodium hydrogen sulphate to afford the corresponding 1,1-diacetates in good to excellent yields. We studied competitive reactions for the acylation of aldehydes in the presence of ketones using silica supported sodium hydrogen sulphate as a catalyst. Using this catalytic system, the highly selective conversion of an aldehyde in the presence of ketone was observed.ConclusionsNaHSO4-SiO2 is a chemoselective and highly efficient catalyst for acylal formation from aldehydes. The advantages of this methodology over the reported methods is the availability of the starting materials, simplicity of acylation procedure, a clean work-up, a short reaction time, high yields and reusability.

Highlights

The concept of green chemistry has been playing an important role in recent years for meeting the fundamental scientific challenges of protecting the living environment
In continuation of our research work to develop new methodologies for organic transformations, [22,23,24,25] we observed that silica supported sodium hydrogen sulphate is a highly efficient catalyst for the synthesis of 1,1-diacetates from the reaction of aldehydes with acetic anhydride under solventfree conditions
We employed the above conditions for the conversion of various aldehydes to the corresponding acylals under solvent-free conditions (Table 1)

Summary

Results

Both aromatic and aliphatic aldehydes reacts smoothly with acetic anhydride in presence of silica supported sodium hydrogen sulphate to afford the corresponding 1,1-diacetates in good to excellent yields. We studied competitive reactions for the acylation of aldehydes in the presence of ketones using silica supported sodium hydrogen sulphate as a catalyst. Using this catalytic system, the highly selective conversion of an aldehyde in the presence of ketone was observed

Conclusions

Introduction

Results and discussions

Conclusion

26. Breton GW