2,3-O-(3-Pentylidene)-D-glyceraldehyde and 2,3-O-(3-Pentylidene)-L-glyceraldehyde: Convenient Glyceraldehyde Surrogates Obtained via a Novel Periodate-Based Oxdation System

The synthesis of two novel glyceraldehyde surrogates, 2,3-O-(3-pentylidene)-D-glyceraldehyde (2) and 2,3-O-(3-pentylidene)-L.-glyceraldehyde (3) is presented. Synthesis, handling and storage advantages of 2 and 3 over the conventionally employed 2,3-O-isopropylidene-D-glyceraldehyde (1) are discussed. The 3-pentanone-derived protecting group facilitates the extraction of product from aqueous oxidation solutions, while the 3-pentanone liberated on ketal deprotection can be efficiently removed at reduced pressures. The synthesis employs a buffered potassium periodate oxidation which offers significant advantages over sodium periodate in glycol cleavage reactions.