Retention of Configuration in Photolytic Decarboxylation of Peresters to Form Chiral Acetals and Ethers

Abstract

Peresters generate ethers in good yields when photolyzed in the absence of solvent using short wavelength UV light. At -78 degrees C or below, the process proceeds predominantly with retention of configuration at the site adjacent to the carbonyl where the decarboxylation occurs, but increase in temperature results in loss of stereochemical control. Chiral acyclic acetals can be prepared using precursors derived from tartaric or malic acids.

Frontal Polymerization: Polymerization Induced Destabilization of Peracrylates

“…For the synthesis of peresters PM and P3 , the methods described by T. I. Yurzhenko et al14 and G. A. Nosaev et al15 were adapted. The peresters P1 , P2 , and PA were prepared by an optimized method from M. D. Spantulescu et al16 Experimental details and spectroscopic data for all the synthesized compounds are given in the Supporting Information.…”

“…The peresters P1, P2, and PA were prepared by an optimized method from M. D. Spantulescu et al [16] Experimental details and spectroscopic data for all the synthesized compounds are given in the Supporting Information.…”

“…Due to low yields of P1, P2 and PA, these peresters were prepared by a coupling reaction of the corresponding acid with tbutyl hydroperoxide using DCC, again similar to a literature method [16] in 69%, 67% and 40% yield, respectively.…”

Synthesis and Characterization of New Azido Esters Derived from Malonic Acid

“…The esterification reactions were now carried out at room temperature via coupling reagent DCC and the respective synthesized azidoalcohols (1)-(3) to increase the yield [12]. The products bis(2-azidoethyl) malonate (bAEM, 4), bis(1,3-diazidopropan-1-yl) malonate (b-1,3-DAPM, 5) and bis(2,3-diazidopropan-1-yl) malonate (b-2,3-DAPM, 6) could be obtained in good yields (over 60 %) without further purification steps [12]. The coupling reactions are shown in Scheme 4.…”

Catalytic Asymmetric Synthesis of Geminal-Dicarboxylates

“…1 The ability to control the stereochemistry of carbon centers featuring two heteroatoms is also important in the development of pharmaceuticals. 1,2 For many years, stereocontrolled access to chiral acetal derivatives relied on derivatisation of chiral starting materials, [3][4][5][6][7][8] metal mediated desymmetrisations, [9][10][11] or kinetic or thermodynamically controlled cyclisation of carbonyl containing chiral-compounds. [12][13][14][15][16][17] A recent approach to bis-heteroatom containing stereogenic centers involves catalysis with very sterically hindered chiral Brønsted acids.…”