R- -Glyceraldehyde

R)-Glyceraldehyde. Fischer projection of, 976 molecular model of, 976, 977 Glyceric acid, structure of. 753 Glycerol, catabolism of, 1132-1133 s/i-Glycerol 3-phosphate, naming of, 1132... 

The substrate-controlled diastereoselective addition of lithiated alkoxyallenes to chiral nitrones such as 123, 125 and 126 (Scheme 8.32) furnish allenylhydroxyl-amines as unstable products, which immediately cydize to give enantiopure mono-orbicyclic 1,2-oxazines (Eqs 8.25 and 8.26) [72, 76]. Starting with (R)-glyceraldehyde-derived nitrone 123, cydization products 124 were formed with excellent syn selectivity in tetrahydrofuran as solvent, whereas precomplexation of nitrone 123 with... 

Most of these operations would yield the enantiomer of 22 in a conformation that is not the mirror image of the original one. However, the need for conformational adjustment is nothing unusual. It is equally necessary if we wish to proceed from the preferred conformation of (R)-glyceraldehyde to that of its enantiomer by exchanging the H and OH ligands. 

Optically pure glyceraldehyde acetonides are widely used in the synthesis of enantiomerically pure compounds (EPC synthesis).1 2 3 4 5 Whereas D-(R)-glyceraldehyde acetonide is easily obtained from the inexpensive D-mannitol,6 7 there are only a limited number of practical syntheses of the enantiomeric L-(S)-glyceraldehyde acetonide.8 9 Difficulties arise from different sources 1) availability of the starting material diisopropylidene-L-mannitol 2) length of the synthesis 10 3) nature of the reactants used mercury acetate, mercaptans, lead tetraacetate, ozone at -78°C, 4) moderate yields.11 14... 

DIASTEREOSELECTIVE HOMOLOGATION OF D-(R)-GLYCERALDEHYDE ACETONIDE USING 2-(TRlMETHYLSILYL)THI AZOLE 2-0-BENZYL-3,4-IS0PR0PYLIDENE-D-ERYTHR0SE (1,3-Dloxolane-4-acetaldehyde, 2,2-dimethyl-a-(phenylmethoxy)-, [R-(R, R )]-)... 

The chiral adduct 753, obtained from the unsaturated oxazolone 632 derived from (R)-glyceraldehyde and Danishefsky s diene, has been conveniently elaborated to the valuable azabicyclic intermediate 844 used for the synthesis of... 

Sv -sclcctivc Michael addition of nitromethane and its homologues to enoates derived from (R)-(+)-glyceraldehyde acetonide (Z)-(102) in the presence of B114N F 3H2O or DBU has been reported to produce mainly. s v -(103) with 80-100% de (Scheme 23). 

Chiral imines have been prepared by reacting (R)-glyceraldehyde acetonide with different co-haloalkylammonium halides. Treatment of the latter with 1.3 equiv. of benzyloxy-, phenoxy- or methoxy acetyl chloride in dichloromethane, in the presence of triethylamine afforded the optically active corresponding (3-lactams (Scheme 38) in high yield and high diastereomeric excess [113]. 

The cyclocondensation of the diene (1) with (R)-glyceraldehyde acetonide (9) results in high asymmetric induction at C5 of the dihydropyrone (10). The configuration (S) was established by degradation to 2-deoxyribonolactone (11). The result is in accord with the Cram rule for addition to chiral carbonyl compounds. The paper also describes conversion of the pyrone (10) to chiral 2,4-dideoxy-D-glucose. 

Chiral ketimines derived from (R)-glyceraldehyde have been cyanated in high de 80... 

R-(+)-Glyceraldehyde is an aldotriose designated by the following Fischer projection formula ... 

The first issue confronted by Myers was preparation of homochiral epoxide 7, the key intermediate needed for his intended nucleophilic addition reaction to enone 6. Its synthesis began with the addition of lithium trimethylsilylacetylide to (R)-glyceraldehyde acetonide (Scheme 8.6).8 This afforded a mixture of propargylic alcohols that underwent oxidation to alkynone 10 with pyridinium dichromate (PDC). A Wittig reaction next ensued to complete installation of the enediyne unit within 11. A 3 1 level of selectivity was observed in favour of the desired olefin isomer. After selective desilylation of the more labile trimethylsilyl group from the product mixture, deacetalation with IN HC1 in tetrahydrofuran (THF) enabled both alkene components to be separated, and compound 12 isolated pure. 

Souza, J. M., and Radi, R., Glyceraldehyde-3-phosphate dehydrogenase inactivation by peroxynitrite. Arch. Biochem. Biophys. 360, 187-194 (1998). 

Alternate Name (R)-glyceraldehyde acetonide, o-glyceraldehyde acetonide, 2,3-O-isopropylidene-D-glyceraldehyde. 

Horizontal bonds come forward. Fischer projection fbrmuia Vertical bonds go back. (R)-glyceraldehyde... 

Further progress towards the stereoselective synthesis of chhydrooxazines has also been reported by Reissig and coworkers who exploited the formal [3 + 3] reaction of lithiated methoxyallene with nitrones derived from (R)-glyceraldehyde [97,98]. Subsequent transformations enabled the synthesis of enantiomerically pure pyrrolidine and 2,5-dihydropyrrole derivatives incorporating one asymmetric unit of the chiral template. 

Dondoni, A, Merino, P, Diastereoselective homologation of D-(R)-glyceraldehyde acetonide using 2-(trimethylsilyl)thiazole 2-0-benzyl-3,4-0-isopropylidene-D-erythrose, Org. Synth., 72, 21-28,... 

Table 10 Addition of Organolithium Reagents to (R)-Glyceraldehyde Acetonide Dimethylhydrazones (149)...

The chiral borolanes ( )- and (Z)-194 (of both R,R and S,S configuration) also show high reagent-controlled diastereoselection in the addition to chiral aldehydes [127 b]. The results obtained from reaction of the substituted borolanes with (R)-glyceraldehyde acetonide (R)-212 are summarized in Table 10-19. The matched... 

---