Abstract: Compositions and methods are provided for the reversible modification of RNA to enhance RNA in-solution and enzymatic stability by reaction with acylimidazoles, sulfonyltriazoles, or sulfonylimidazoles. 2?-OH acylation protects RNA from hydrolytic and enzymatic degradation. Water-soluble organocatalysts can accelerate the reversal of acylation adducts and functionally restore RNAs, alternatively the acylation is spontaneously reversed in a cellular environment. Chemically tuned 2?-OH acylation can be spontaneously released in cells to restore RNA biological functions including translation. mRNA can be selectively modified at the 2?-OH of poly(A)-tail for enhanced in-cell stability and enhanced total protein output.