D- -Glyceraldehyde acetonide

An allylcadmium reagent was reported to add to D-glyceraldehyde acetonide with high Cram selectivity and moderate regioselectivity58. 

Figure 10. Reactions of allyl- and crotylboronates with D-glyceraldehyde acetonide (23).

Figure 13. Reaction of D-glyceraldehyde acetonide with tartrate allylboronate 36.

Adduct 33 has been exploited in the synthesis of the antiretroviral agent 34100 (equation 24), while ent-33, obtained from D-glyceraldehyde acetonide (ent-32), was converted into 35, a fluoro analogue of 2-deoxyribonolactone, a DNA lesion product101 (equation 25). 

On reaction with D-glyceraldehyde acetonide in the presence of a Lewis acid at —90 °C, the silyloxythiophene gave the A,h-threoS,(i-erythroA%Qmci 208 (d.s. >95%) along with a small amount of the other diastereomer. This reaction has been used for the synthesis of the thio analog 209 of the natural product muricatacin (Scheme 56) <1997JOC4513>. 

Dondoni and coworkers [63] have shown that homologation of a-hydroxycarbaldehydes can be achieved with high antiselectivity by addition of 2-(trimethylsilyl)thiazole (42) (Scheme 13.25). For instance, D-glyceraldehyde acetonide (R)-24 reacts with 42 giving 43 in 96% yields with the anti vs. syn diastereoselectivity better than 95 5. Release of the aldehyde requires protection of the alcohol as a benzyl ether, methylation of the thiazole generates intermediate 43 Me that is not isolated but reduced in situ with NaBH4 to give thiazoline 43 H. Mercury(II)-catalyzed hydrolysis liberate the semiprotected D-erythrose derivative d-45 in 62% overall yield [64]. Methylation of the thiazole moiety can also be achieved with methyl triflate instead of Mel, and copper(II)chloride can be used instead of mercury(II)chloride [65]. 

An aminohomologation of carbaldehydes was developed by Dondoni and coworkers, thus remarkably extending the scope of their one-carbon chain-elongation method (Scheme 13.28). For example, the A-benzylnitrone 53, derived from D-glyceraldehyde acetonide (R)-24, was added to... 

SCHEME 13.29 Anti and syn diastereoselective vinylations of D-glyceraldehyde acetonide. 

Kusakabe, M, Sato, F, Stereoselective synthesis of D-erythrose and D-threose derivatives from D-glyceraldehyde acetonide and their reactions with l-(trimethylsiyl)vinyl cuprate reagent. Synthesis of allitol acetate, Chem. Lett., 1473-1476, 1986. 

A. Dondoni and P. Merino, Diastereoselective homologation of D-() )-glyceraldehyde acetonide using 2-(trimethylsilyl)thiazole 2-0-benzyl-3,4,-0-isopropylidene-D-erythrose, Org. Synth. 72 21 (1993) The procedure has been checked by A. I. Meyers and G. P. Brengel, Colorado State University, USA. 

The first examples of highly diastereoselective double asymmetric reactions involving chiral allyl metal reagents were obtained in reactions with D-glyceraldehyde acetonide (151 Table 6). Aldehyde (151) displays an 80 20 preference for (154) in reactions with the achiral pinacol allylboronate (144 entry 4),25.ioi selectivity for (154) improves to 96-98% with reagents (-)-(215) and (RJi)-... 

Table 6 Reactions of D-Glyceraldehyde Acetonide (151) and Chiral Allyl Metal Reagents...

Synthesisfromo-glyceraldehyde D-Glyceraldehyde acetonide (17) has been used for the synthesis of a protected nectrisine 23 (Scheme 4). Compound 17 was converted into 3,3-diethoxy-2-hydroxypropanal (18), which underwent transketolase-mediated condensation with hydroxypyruvate 19 to afford the triol 20 in 56% yield. Silylation of 20 using TBSOTf and NEts (74%) followed by treatment with hydroxylamine gave the oxime 21 in 82% yield. Reduction of 21 using Raney nickel afforded the diastereomeric mixture of... 

Synthesis from o-glyceraldehyde Synthesis of (-)-prosophylline (1) from D-glyceraldehyde acetonide (64) has been reported (Scheme 7). The enantioselective al-lylation of aldehyde 64 with (S,S)-75 afforded the homoallyl alcohol 65 in 86% yield. Protection of 65, as the benzyl derivative, followed by hydroboration and transformation to... 

D-Glyceraldehyde acetonide (118) has also been used for the synthesis of other (3-lactams (Scheme 14). It was converted into the Schiff base 129, followed by reaction with potassium azidoacetate, cyanuric chloride and triethylamine to give the p-lactam 130 as a single c/s-isomer in 55% yield. The reaction of 130 with methoxyacetyl chloride in the presence of triethylamine afforded the cw-p-lactam 131. Similarly, c/ -p-lactams 131-135 were also prepared as single isomers in comparable yields. Acid hydrolysis of 130 afforded 136, which underwent oxidation of the diol side chain and then removal of the p-methoxybenzyl group with CAN to afford 137. The allyl derivative 135 was oxidized to... 

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