Exemplified by block buster GLP-1 agonists (e.g. semaglutide),1 peptides have undeniably gained importance in modern therapeutics. Their synthesis, however, continues to pose various challenges and necessitates the development of innovative synthetic methods.2,3 In particular, novel approaches are needed to reduce the environmental footprint of laboratory research and industrial manufacture of peptides, which produces hazardous solvent waste at a large scale.3,4 Hence, the emergence of aqueous solid phase peptide synthesis (ASPPS) platform is a promising step forward in the greening of peptide chemistries, leveraging the Smoc group for Nα-protection.5 However, many aspects require further optimisation before ASPPS is likely to see the widescale implementation of the traditional Fmoc-SPPS platforms. Specifically, there is a need for water-compatible and efficient orthogonal protecting strategies for amines that reduce or eliminate hazardous solvent waste generated from the currently prevalent orthogonal deprotection schemes of amines. 1,3-dicarbonyl chemistries are well-established as versatile routes to heterocycles and carbocycles,6,7 however, these techniques remain minimally explored in peptide synthesis or modification. Herein, we aimed to leverage the expanse of 1,3-dicarbonyl chemistries to address this highly criticised unsustainability of peptide drug production. This study adopts a 1,3-dicarbonyl group as a new amine protecting group strategy that is orthogonal to common Nα-protecting groups, demonstrates high atom economy, and is removed efficiently in green solvents such as water or water/alcohol mixtures. This approach, along with the advances of ASPPS, lends opportunity to robustly assemble branched, cyclic, and modified peptide frameworks in completely water-based media.