Merging Photoredox Catalysis with Organocatalysis: The Direct Asymmetric Alkylation of Aldehydes
Science, 2008 · paper · Chemistry
Combines a ruthenium photoredox catalyst with an imidazolidinone organocatalyst to alkylate aldehydes at the α-position. The authors report a broadly applicable, previously elusive reaction that is highly enantioselective and operationally simple.
1 finding
Wording Table 1 caption defines "Boc, tert-butyl carbamoyl."; Boc is tert-butoxycarbonyl (the N-Boc group in entry 5 is a tert-butyl carbamate, and the text itself lists "carbamates").
- p. 8 Table 1 caption
Boc, tert-butyl carbamoyl
- p. 8 Table 1, entry 5 structure
NBOC
- p. 8 Table 1 caption, abbreviation list
Boc, tert-butyl carbamoyl.
Judge's note: Page 8 image shows the caption as quoted. Entry 5 draws a piperidine nitrogen bearing Boc, and page 3 describes the functionality as a carbamate. "Carbamoyl" names an aminocarbonyl group (R2N-C(=O)-), a different substituent from the alkoxycarbonyl group that Boc abbreviates. The expansion rests on standard nomenclature, not on anything stated in the files. The NBOC/Boc capitalisation point raised here is handled under C014.
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11 minor (typos and the like; most checked by the judge only)
Typo The corresponding author's surname is printed "David W. C. MacMilla*" in the byline and "Nicewicz and MacMilla" in the running heads; the paper's own references 6-8 print "MacMillan DWC".
- p. 1 author byline
David W. C. MacMilla
- p. 2 running head
Nicewicz and MacMilla
- p. 4 reference 6
MacMillan DWC
- p. 1 Author byline
David W. C. MacMilla*
Judge's note: Page 1 image shows the byline "MacMilla" followed directly by the asterisk. The running heads on pages 2, 3, 4 and 8 read "Nicewicz and MacMilla". References 6, 7 and 8 on page 4 spell the name "MacMillan DWC" and the e-mail is dmacmill@princeton.edu. The final n is missing. This is the NIH author-manuscript rendering, so the truncation may come from the PMC conversion and not the Science version, but it is in this PDF.
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Typo Fig. 1 caption reads "Merging amine catalysis and organometallic photoredox catalysis", while the text calls Ru(bpy)3 2+ "an inorganic complex" (page 1) and the approach "the marriage of inorganic electron transfer and organic catalysis (Fig. 1)" (page 2).
- p. 6 Fig. 1 caption
Merging amine catalysis and organometallic photoredox catalysis
- p. 1 Introduction, first paragraph
an inorganic complex that has facilitated important advances
- p. 2 Sentence citing Fig. 1
the marriage of inorganic electron transfer and organic catalysis (Fig. 1)
Judge's note: All three passages confirmed on the images. The caption and the sentence that cites the figure classify the same catalyst differently. "Organometallic" is often used loosely for metal complexes with organic ligands, so either form could stand; a terminology inconsistency only.
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Typo Missing space between sentences: "ee).Whereas α-bromo esters are readily tolerated".
- p. 3 second paragraph (bromide scope), line 5
ee).Whereas α-bromo esters are readily tolerated
- p. 3 Results, α-bromo carbonyl scope paragraph
ee).Whereas α-bromo esters
Judge's note: Page 3 image, second paragraph: the line begins "ee).Whereas" with no space after the full stop. It is mid-line, not a line-join artefact.
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Typo Superfluous comma before a parenthesis: "all-carbon quaternary centers, (entries 11 and 12, ≥70% yield, 88 to 99% ee)."
- p. 3 second paragraph (bromide scope)
all-carbon quaternary centers, (entries 11 and 12
Judge's note: Page 3 image shows the comma directly before the opening parenthesis, with the sentence ending after the closing parenthesis. Punctuation only.
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Typo One reagent is named two ways: "octanal and bromo diethylmalonate" (page 3, first full paragraph) and "diethyl bromomalonate" (page 3 control experiments, page 4, Table 1 footnote).
- p. 3 first full paragraph
octanal and bromo diethylmalonate as the coupling partners
- p. 3 control-experiments paragraph
α-bromoacetophenone or diethyl bromomalonate
- p. 8 Table 1 footnote *
Reactions performed with diethyl bromomalonate.
- p. 3 Results, first paragraph on the protocol
octanal and bromo diethylmalonate
Judge's note: Page 3 image shows "bromo diethylmalonate" at first mention and "diethyl bromomalonate" in the control-experiments paragraph. Page 4 and the Table 1 footnote on page 8 ("Reactions performed with diethyl bromomalonate.") use the second form. Same compound, so meaning is unaffected; a naming inconsistency only.
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Typo Reference 16 is malformed: "Renaud P, Schubert S. Synlett 1990;6241990" (page number run into a repeated year, no separator or closing full stop).
- p. 4 References and Notes, ref 16
Renaud P, Schubert S. Synlett 1990;6241990
- p. 4 References, ref 16
Synlett 1990;6241990
Judge's note: Page 4 image shows the entry exactly as quoted. Every other journal entry follows year;volume:page (for example "J. Org. Chem 1991;56:3475."). The string reads as page 624 fused with the year 1990. The malformation is evident on the page; that the intended first page is 624 is an inference from the string and was not checked against an outside source.
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Typo Reference 6 prints "[PubMed: 17395791]published online 28 March 2007 (10.1126/science. 1142696).": a space inside the DOI and no space before "published".
- p. 4 References and Notes, ref 6
17395791]published online 28 March 2007 (10.1126/science. 1142696)
- p. 4 References, ref 6
10.1126/science. 1142696
Judge's note: Page 4 image: the space after "science." falls mid-line, not at the line wrap, and "]published" has no separating space. The paper's own DOI on page 1 is printed without a space ("doi:10.1126/science.1161976").
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Typo Note 31 names the fellowship "NIH National Service Research Award fellowship (F32GM076816)"; the words "Service" and "Research" appear transposed.
- p. 5 note 31 (acknowledgements)
NIH National Service Research Award fellowship (F32GM076816)
Only the authors can say what is right here.
Judge's note: Rests on outside knowledge: the NIH F32 fellowship is named the Ruth L. Kirschstein National Research Service Award (NRSA). The crop of page 5 shows the text as quoted, "NIH National Service Research Award fellowship (F32GM076816)". Nothing in the files states the award's official name.
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Typo Table 1 caption expands DMF as "N,N′-dimethylformamide"; the compound is N,N-dimethylformamide (both methyl groups on the single nitrogen).
- p. 8 Table 1 caption
DMF, N,N ′-dimethylformamide
Judge's note: Page 8 image: the caption reads "DMF, N,N" at the line end and "′-dimethylformamide" at the start of the next line, so the prime is printed. Formamide has one nitrogen, so a primed locant has no referent. Standard nomenclature; the scheme in the same table shows DMF only as the solvent.
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Typo Table 1, entry 10: the bromide's ester group is labelled "F3CH2CO", while the product in the same row is labelled "OCH2CF3"; the reversed form of the trifluoroethoxy group is F3CCH2O.
- p. 8 Table 1, entry 10, α-bromocarbonyl structure
F3CH2CO
- p. 8 Table 1, entry 10, product structure
OCH2CF3
Judge's note: Enlarged the entry at 400 dpi from the PDF: the left-hand label reads F3CH2CO attached to the carbonyl carbon, and the product reads OCH2CF3. The text on page 3 calls the substrate "the trifluoroethyl ester". As printed, the label has the second carbon and the H2 transposed. The structure is still unambiguous from the product and the text, so cosmetic.
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Typo Table 1, entry 5: the protecting group is labelled "NBOC" on the aldehyde and "Boc" on the product; the caption defines only "Boc".
- p. 8 Table 1, entry 5, aldehyde structure
NBOC
- p. 8 Table 1, entry 5, product structure
Boc
Judge's note: Enlarged the entry at 400 dpi from the PDF: the aldehyde's piperidine is labelled NBOC in capitals and the product's nitrogen is labelled Boc. Capitalisation differs within one row; the meaning is clear.
Second check: none (judge only)