672-13-9

Basic information

• Product Name: 2-Hydroxy-5-methoxybenzaldehyde
• Synonyms: 2-Formyl-4-methoxyphenol;2-hydroxy-5-methoxy-benzaldehyd;6-hydroxy-m-anisaldehyd;m-Anisaldehyde, 6-hydroxy-;Salicylaldehyde, 5-methoxy-;5-METHOXYSALICYLALDEHYDE;5-METHOXY-2-HYDROXY BENZALDEHYDE;6-HYDROXY-3-ANISALDEHYDE
• CAS NO: 672-13-9
• Molecular Formula: C₈H₈O₃
• Molecular Weight: 152.15
• EINECS: 211-589-0
• Product Categories: Aromatic Aldehydes & Derivatives (substituted);Benzaldehyde;Adehydes, Acetals & Ketones;Anisoles, Alkyloxy Compounds & Phenylacetates;Phenols
• Mol File: 672-13-9.mol
• Article Data: 73

Chemical Properties

• Melting Point: 4 °C(lit.)
• Boiling Point: 103 °C2.5 mm Hg(lit.)
• Flash Point: >230 °F
• Appearance: Clear yellow/Liquid
• Density: 1.219 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.0162mmHg at 25°C
• Refractive Index: n20/D 1.578(lit.)
• Storage Temp.: Store below +30°C.
• PKA: 8.66±0.18(Predicted)
• Water Solubility: Miscible with chloroform. Slightly miscible with water.
• Sensitive: Air Sensitive
• BRN: 1100532
• CAS DataBase Reference: 2-Hydroxy-5-methoxybenzaldehyde(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Hydroxy-5-methoxybenzaldehyde(672-13-9)
• EPA Substance Registry System: 2-Hydroxy-5-methoxybenzaldehyde(672-13-9)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36-24/25
• WGK Germany: 3
• RTECS: BZ2800000
• F: 10-23
• Hazardous Substances Data: 672-13-9(Hazardous Substances Data)

Usage

Chemical Properties

clear yellow liquid

Uses

Different sources of media describe the Uses of 672-13-9 differently. You can refer to the following data:
1. 2-Hydroxy-5-methoxybenzaldehyde is employed to study electroantennogram response of the vine weevil (Otiorhynchus sulcatus F) to a broad range of volatile plant compounds. It plays an important role in the preparation of tetradentate Schiff base compounds. Further, it is used in the preparation 6-methoxy-3-nitro-2H-chromene by using dibutylamine as a reagent.
2. 2-Hydroxy-5-methoxybenzaldehyde was used to synthesize radiolabeling precursor desmethyl-PBR06. It was used to study electroantennogram response of the vine weevil (Otiorhynchus sulcatus F.) to a broad range of volatile plant compounds. It was used in the synthesis of tetradentate Schiff base compounds.

General Description

2-Hydroxy-5-methoxybenzaldehyde has acaricidal activity against Tyrophagus putrescentiae.

InChI:InChI=1/C8H8O3/c1-11-7-2-3-8(10)6(4-7)5-9/h2-5,10H,1H3

Synthetic route

formaldehyd (50-00-0) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Stage #1: formaldehyd With triethylamine; magnesium chloride In tetrahydrofuran at 20℃; for 0.166667h; Inert atmosphere; Reflux; Stage #2: 4-methoxy-phenol In tetrahydrofuran Reflux;	100%
Stage #1: formaldehyd With triethylamine; magnesium chloride In tetrahydrofuran at 20 - 25℃; for 0.166667h; Stage #2: 4-methoxy-phenol In tetrahydrofuran Reflux;	100%
Stage #1: formaldehyd With triethylamine; magnesium chloride In tetrahydrofuran at 20℃; for 0.25h; Inert atmosphere; Stage #2: 4-methoxy-phenol In tetrahydrofuran for 16h; Inert atmosphere; Reflux;	99%

2,5-dimethoxybenzaldehyde (93-02-7) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With aluminum (III) chloride In dichloromethane at 20℃; for 12h; Inert atmosphere;	98%
With aluminum (III) chloride In dichloromethane at 20℃; for 12h; Inert atmosphere;	98%
With beryllium(II) chloride In toluene for 7h;	95%
With aluminium(III) iodide; N,N-dimethyl-formamide dimethyl acetal In acetonitrile at 80℃; for 18h;	47%
Stage #1: 2,5-dimethoxybenzaldehyde With aluminum (III) chloride In dichloromethane at 0 - 20℃; for 4h; Stage #2: With water In dichloromethane at 0℃;

2-hydroxy-5-methoxybenzyl alcohol (41951-76-2) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With air; (acryl-TEMPO)-co-(allylamine-treated chlorophyll b-Co(III) complex) immobilized on SiO2-covered Fe3O4 magnetic nanoparticles In water at 25℃; for 0.416667h;	96%
With oxygen In ethanol at 20℃; under 760.051 Torr; for 0.5h; Catalytic behavior; Green chemistry;	95%
With dihydrogen peroxide at 20℃; for 3.6h; Catalytic behavior; Green chemistry;	94%

chloroform (67-66-3) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With sodium hydroxide In water for 1h; Heating;	72%
With sodium hydroxide Reimer-Tiemann reaction; Heating;	65%
With sodium hydroxide at 70 - 80℃; for 0.5h;	48%

1-(o-hydroxy-5-methoxyphenyl)-3-phenylpropargylic alcohol (133503-46-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 1,4-diphenyl-1,3-butadiyne (886-66-8)

Conditions	Yield
With copper(II) acetate monohydrate In acetonitrile for 2h; Reflux;	A n/a B 72%

5-methoxy-2-(prop-2-yn-1-yloxy)benzaldehyde (224317-65-1) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 2-(1-hydroxybut-3-yn-1-yl)-4-methoxyphenol

Conditions	Yield
With tetrabutylammonium tetrafluoroborate; tris(2,2'-bipyridine)nickel(II) tetrafluoroborate In N,N-dimethyl-formamide electrochem. reaction; magnesium rod anode, nickel foam grid cathode;	A 30% B 65%

4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Reimer-Tiemann reaction;	60%
Multi-step reaction with 2 steps 1: 40 percent / BF3*Et2O / CH2Cl2 / 14 h / Ambient temperature 2: 47 percent / H2O, HgO, BF3*Et2O / tetrahydrofuran / 1 h / Ambient temperature View Scheme

2-[1,3]Dithiolan-2-yl-4-methoxy-phenol (80210-54-4) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With boron trifluoride diethyl etherate; water; mercury(II) oxide In tetrahydrofuran for 1h; Ambient temperature;	47%

hexamethylenetetramine (100-97-0) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 2-hydroxy-5-methoxyisophthaldehyde (73289-61-9)

Conditions	Yield
In trifluoroacetic acid for 24h;	A n/a B 32%

hexamethylenetetramine (100-97-0) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
in ein zuvor auf 165grad erhitztes Gemisch von Glycerin und Borsaeure bei 150grad und Behandeln des Reaktionsgemisches mit wss.H2SO4 bei 115grad;
With toluene-4-sulfonic acid In acetic acid for 5h; Duff Aldehyde Synthesis; Reflux; Inert atmosphere;

2,5-Dihydroxybenzaldehyde (1194-98-5) + dimethyl sulfate (77-78-1) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 2,5-dimethoxybenzaldehyde (93-02-7)

Conditions	Yield
With sodium hydroxide

5-methoxysalicylic acid (2612-02-4) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
(i) SOCl2, Py, PE, (ii) H2, quinoline, sulfur, Pd-BaSO4, xylene; Multistep reaction;

tris(phenylthio)methane (4832-52-4) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With dimethyl(methylthio)sulfonium tetrafluoroborate; water 1.) CH2Cl2, room temp., 2 h; Yield given. Multistep reaction;

N,N-diethyl-O-(4-methoxyphenyl)carbamate (85630-18-8) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + O-(2-formyl-4-methoxy)phenyl N,N-diethylcarbamate (85630-27-9)

Conditions	Yield
With N,N,N,N,-tetramethylethylenediamine; sec.-butyllithium 1.) THF, -78 deg C, 1 h, 2.) to room temp., 8 to 12 h; Yield given. Multistep reaction. Yields of byproduct given;

2-t-butoxy-5-methoxybenzaldehyde (98751-26-9) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With trifluoroacetic acid

2-Acetoxy-benzoic acid 2-formyl-4-methoxy-phenyl ester → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + aspirin (50-78-2)

Conditions	Yield
With hydroxide In 1,4-dioxane; water at 37℃; Rate constant; Thermodynamic data; var. temp., ΔH(excit.), ΔS)(excit.);

4-methoxy-phenol (150-76-5) + paraformaldehyde → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With ethylmagnesium bromide; triethylamine 1.) THF, RT, 20 min, 2.) C6H6, reflux, 2.5 h; Yield given. Multistep reaction;

2-acetoxy-5-methoxybenzaldehyde (62536-85-0) + alkali → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + acetic acid (64-19-7)

2-iodo-5-methoxybenzaldehyde (77287-58-2) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: 12 percent / t-BuOK, CuCl, pyridine / 1,2-dimethoxy-ethane / 3 h / Heating 2: CF3COOH View Scheme
Multi-step reaction with 2 steps 1: 1.) CuCl, 2.) pyridine, 1,3-dinitrobenzene / 1.) DME, 2.) reflux, 3 h 2: CF3COOH View Scheme

3-methoxy-benzaldehyde (591-31-1) + 2-oxy-phenylacetate sodium → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Multi-step reaction with 3 steps 1: 59 percent / I2, H5IO6 / acetic acid; H2O; H2SO4 / 2 h / 80 °C 2: 12 percent / t-BuOK, CuCl, pyridine / 1,2-dimethoxy-ethane / 3 h / Heating 3: CF3COOH View Scheme
Multi-step reaction with 3 steps 1: 59 percent / I2, H5IO6 / acetic acid; H2O; H2SO4 / 2 h / 80 °C 2: 1.) CuCl, 2.) pyridine, 1,3-dinitrobenzene / 1.) DME, 2.) reflux, 3 h 3: CF3COOH View Scheme

meta-hydroxybenzaldehyde (100-83-4) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: potassium persulfate; NaOH-solution; alkali / 30 - 35 °C / und Erhitzen des Reaktionsprodukts mit konz.Salzsaeure auf 70grad 2: aqueous NaOH-solution View Scheme

4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + Hg

2-(2-hydroxy-5-methoxyphenyl)-4-phenoxymethyl-1,3-dioxolane (1079921-21-3) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 1-phenoxy-2,3-propanediol (538-43-2)

Conditions	Yield
With water In methanol at 20℃; Quantum yield; Irradiation;	A n/a B 96 %Chromat.

2-(2-hydroxy-5-methoxyphenyl)-5-phenyl-1,3-dioxane (1079921-26-8) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 2-phenylpropane-1, 3-diol (1570-95-2)

Conditions	Yield
With water In methanol at 20℃; Quantum yield; Irradiation;	A n/a B 59 %Chromat.

2-(2-hydroxy-5-methoxyphenyl)-1,3-dioxolane (773101-17-0) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + ethylene glycol (107-21-1)

Conditions	Yield
With water In methanol at 20℃; Quantum yield; Irradiation;	A n/a B 100 %Spectr.

2-(2-hydroxy-5-methoxyphenyl)-5,5-dimethyl-1,3-dioxane (1079921-29-1) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 2,2-Dimethyl-1,3-propanediol (126-30-7)

Conditions	Yield
With water In methanol at 20℃; Quantum yield; Irradiation;	A n/a B 100 %Spectr.

N,N-dimethyl-formamide (68-12-2, 33513-42-7) + 4-methoxy-2-(trimethylsilyl)phenyl triflate → 2-Hydroxy-4-methoxybenzaldehyde (673-22-3) + 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
Stage #1: N,N-dimethyl-formamide; 4-methoxy-2-(trimethylsilyl)phenyl triflate With tetrabutyl ammonium fluoride at 20℃; for 3h; Inert atmosphere; Stage #2: With water

ethanol (64-17-5) + 4-methoxy-phenol (150-76-5) → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With chloroform; potassium hydroxide In water at 60℃; for 15h; Reimer-Tiemann Phenol Formylation;

4-methoxy-phenol (150-76-5) + polyformaldehyde → 2-hydroxy-5-methoxybenzaldehyde (672-13-9)

Conditions	Yield
With magnesium chloride In acetonitrile Reflux;

2-hydroxy-5-methoxybenzaldehyde (672-13-9) → 1-hydroxy-4-methoxy-2-methylbenzene (5307-05-1)

Conditions	Yield
Stage #1: 2-hydroxy-5-methoxybenzaldehyde With chloroformic acid ethyl ester; triethylamine In tetrahydrofuran at 0℃; for 1h; Stage #2: With sodium tetrahydroborate In tetrahydrofuran; water at 20℃; for 2.25h; Cooling with ice; Stage #3: With hydrogenchloride In tetrahydrofuran; water pH=< 2;	100%
With potassium hydroxide; hydrazine In ethylene glycol at 150℃; for 19h; Wolf-Kishner reduction; Inert atmosphere;	98%
With palladium 10% on activated carbon; hydrogen In acetic acid; ethyl acetate at 20℃; for 20h;	98%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + acrylonitrile (107-13-1) → 6-methoxy-2H-chromene-3-carbonitrile (57543-71-2)

Conditions	Yield
With 1,4-diaza-bicyclo[2.2.2]octane for 20h; Heating;	100%
With 1,4-diaza-bicyclo[2.2.2]octane for 12h; Reflux;	91.3%
With 1,4-diaza-bicyclo[2.2.2]octane at 50℃; for 20h; Addition; condenzation;	79%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + allyl bromide (106-95-6) → 2-allyloxy-5-methoxybenzaldehyde (71186-59-9)

Conditions	Yield
With potassium carbonate In tetrahydrofuran Inert atmosphere; Reflux;	100%
With potassium carbonate In acetonitrile Heating;	99%
With potassium carbonate In acetonitrile for 1h; Heating;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + propargyl bromide (106-96-7) → 5-methoxy-2-(prop-2-yn-1-yloxy)benzaldehyde (224317-65-1)

Conditions	Yield
With potassium carbonate In acetone Substitution; Heating;	100%
With potassium carbonate In N,N-dimethyl-formamide at 70℃; for 3h; Inert atmosphere;	100%
With potassium carbonate In acetonitrile at 20℃; for 24h;	95%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + benzyl bromide (100-39-0) → 2-benzyloxy-5-methoxybenzaldehyde (56979-57-8)

Conditions	Yield
With sodium hydride In tetrahydrofuran; mineral oil at 60℃; Inert atmosphere;	100%
With caesium carbonate In acetone at 20℃;	100%
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 24h;	100%

9-ethyl-3-[(E)-2-nitrovinyl]-9H-carbazole + 2-hydroxy-5-methoxybenzaldehyde (672-13-9) → 9-ethyl-3-(6-methoxy-3-nitro-2H-chromen-2-yl)-9H-carbazole

Conditions	Yield
With 1,4-diaza-bicyclo[2.2.2]octane at 70℃; for 0.5h;	100%

5-methylisoxazol-3-ylamine (1072-67-9) + 2-hydroxy-5-methoxybenzaldehyde (672-13-9) → 4-methoxy-2-[(5-methyl-3-isoxazolyl)imino]methylphenol (415715-07-0)

Conditions	Yield
Reflux;	100%
In ethanol for 2h; Reflux;	90%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + {(1R,3R,4S,6S)-4-amino-4,7,7-trimethylbicyclo[4.1.0]heptan-3-yl}methanol (654680-82-7) → 2-[(1S,3S,4R,6R)-4-hydroxymethyl-3,7,7-trimethylbicyclo[4.1.0]heptan-3-yliminomethyl]-4-methoxyphenol

Conditions	Yield
In methanol at 20℃; for 24h;	100%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) → 2-hydroxy-5-methoxybenzyl alcohol (41951-76-2)

Conditions	Yield
With sodium tetrahydroborate In ethanol at 20℃; for 1h;	99.7%
With sodium tetrahydroborate	85%
With sodium tetrahydroborate In ethanol at 20℃; Cooling with ice;	85%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + diethyl malonate (105-53-3) → 6-methoxycoumarin-3-carboxylic acid (35924-44-8)

Conditions	Yield
Stage #1: 2-hydroxy-5-methoxybenzaldehyde; diethyl malonate With piperidine; acetic acid In ethanol for 9h; Reflux; Stage #2: With ethanol; water; sodium hydroxide for 0.25h; Reflux;	99.2%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + prenyl bromide (870-63-3) → 5-methoxy-2-(3-methylbut-2-enyloxy)benzaldehyde (139579-42-3)

Conditions	Yield
With potassium carbonate; potassium iodide In N,N-dimethyl-formamide Ambient temperature;	99%
With potassium carbonate; potassium iodide In N,N-dimethyl-formamide at 20℃; for 2h;
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 48h;
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 48h;
Stage #1: 2-hydroxy-5-methoxybenzaldehyde With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 0.25h; Stage #2: prenyl bromide In N,N-dimethyl-formamide at 20℃;

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + N,N-phenylbistrifluoromethane-sulfonimide (37595-74-7) → trifluoro-methanesulfonic acid 2-formyl-4-methoxy-phenyl ester (424788-79-4)

Conditions	Yield
With dmap; triethylamine In dichloromethane at 0 - 20℃; for 0.5h; Inert atmosphere;	99%
With potassium carbonate In tetrahydrofuran at 120℃; for 0.1h; microwave heating;	87%
With triethylamine
With potassium carbonate In tetrahydrofuran at 120℃; for 0.1h; Microwave irradiation;

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + p-toluenesulfonyl chloride (98-59-9) → toluene-4-sulfonic acid 2-formyl-4-methoxy-phenyl ester (329235-34-9)

Conditions	Yield
With sodium hydroxide In dichloromethane; water Inert atmosphere;	99%
With potassium carbonate In acetonitrile at 20℃; for 12h;	91%
With sodium hydroxide In dichloromethane; water at 20℃;	71%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + tert-butyldimethylsilyl chloride (18162-48-6) → 2-tert-butyldimethylsiloxy-5-methoxyphenyl carboxaldehyde (441068-94-6)

Conditions	Yield
With 1H-imidazole In dichloromethane at 25℃; for 16h; Inert atmosphere;	99%
With N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 20℃; for 0.5h;	97%
With 1H-imidazole In N,N-dimethyl-formamide at 80℃; for 20h;	90%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + malononitrile (109-77-3) → 2-(2-Amino-3-cyano-6-methoxy-4H-chromen-4-yl)-malononitrile

Conditions	Yield
With poly(N,N'-dibromo-N-ethyl-benzene-1,3-disulfonamide) In ethanol; water at 20℃; for 3h;	99%
With diethylamine In ethanol at 20℃; for 2.5h; Green chemistry;	94%
With piperidine In ethanol at 20℃;

O-Merrifield resin-bound 4-(2\-acetoacetylethyl)phenol + 2-hydroxy-5-methoxybenzaldehyde (672-13-9) → 3-acetyl-6-methoxycoumarin (13252-80-7)

Conditions	Yield
With piperidine In ethanol for 2.5h; Knoevenagel condensation; Heating;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 4-bromoethylbutanoate (2969-81-5) → ethyl 4-(2-formyl-4-methoxyphenoxy)butanoate (356039-75-3)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 90℃; for 1h;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + ethyl 5-bromovalerate (14660-52-7) → ethyl 5-(2-formyl-4-methoxyphenoxy)pentanoate

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 90℃; for 1h;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + benzoyl chloride (98-88-4) → 2-formyl-4-methoxyphenyl benzoate

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 1h; Inert atmosphere; Schlenk technique;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 4-chlorobenzoyl chloride (586-75-4) → 2-formyl-4-methoxyphenyl 4-bromobenzoate

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 1h; Inert atmosphere; Schlenk technique;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 4-methoxy-benzoyl chloride (100-07-2) → 2-formyl-4-methoxyphenyl 4-methoxybenzoate

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 1h; Inert atmosphere; Schlenk technique;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) → (E)-5-methoxy-2-hydroxybenzaldehyde oxime (66384-65-4)

Conditions	Yield
With pyridine; hydroxylamine hydrochloride In ethanol at 60℃; for 3h; Inert atmosphere;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + norbornene (498-66-8) → C15H18O3

Conditions	Yield
With [(1,5-cyclooctadiene)(OH)iridium(I)]2 In 1,4-dioxane at 60℃; for 6h; Inert atmosphere; Schlenk technique; Sealed tube; diastereoselective reaction;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + C15H13N3O2 → 6-methoxy-3-(4-methoxyphenyl)-2H-chromen-2-one (263364-71-2)

Conditions	Yield
With triethylamine In neat (no solvent) at 20℃; for 0.0833333h; Sonication;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + Cinnamyl bromide (4392-24-9) → 2-allyloxy-5-methoxybenzaldehyde (71186-59-9)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 18h;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 4-hydroxy-1-methyl-2(1H)-quinolone (1677-46-9) + tributylphosphine (998-40-3) → 3-((2-hydroxy-5-methoxyphenyl)(tributylphosphonio)methyl)-1-methyl-2-oxo-1,2-dihydroquinolin-4-olate

Conditions	Yield
With pyrrolidine; benzoic acid In tetrahydrofuran at 30℃; for 1h; Schlenk technique; Inert atmosphere;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + propylmaleimide (21746-40-7) + D-alanine methyl ester hydrochloride (14316-06-4) → methyl (1R,3S,3aR,6aS)-3-(2-hydroxy-5-methoxyphenyl)-1-methyl-4,6-dioxo-5-propyloctahydropyrrolo[3,4-c]pyrrole-1-carboxylate

Conditions	Yield
With triethylamine In acetonitrile at 125℃; for 0.5h; Microwave irradiation; Green chemistry; diastereoselective reaction;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + ethyl 2-amino-3-phenylpropanoate hydrochloride (3182-93-2) → ethyl (E)-2-((2-hydroxy-5-methoxybenzylidene)amino)-3-phenylpropanoate

Conditions	Yield
With triethylamine In acetonitrile at 20℃; for 24h; Inert atmosphere;	99%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + ethyl (triphenylphosphoranylidene)acetate (1099-45-2) → 6-methoxycoumarin (17372-53-1)

Conditions	Yield
With N,N-diethylaniline Wittig reaction; Reflux;	98%
With N,N-diethylaniline at 210 - 215℃; for 2.5h;	93.4%
With N,N-diethylaniline for 2.5h; Heating;	93%

Upstream product

• 62536-85-0 2-acetoxy-5-methoxybenzaldehyde 
• 1079921-21-3 2-(2-hydroxy-5-methoxyphenyl)-4-phenoxymethyl-1,3-dioxolane 
• 1079921-26-8 2-(2-hydroxy-5-methoxyphenyl)-5-phenyl-1,3-dioxane 
• 773101-17-0 2-(2-hydroxy-5-methoxyphenyl)-1,3-dioxolane 
• 1079921-29-1 2-(2-hydroxy-5-methoxyphenyl)-5,5-dimethyl-1,3-dioxane 
• 68-12-2 N,N-dimethyl-formamide 
• 556812-41-0 4-methoxy-2-(trimethylsilyl)phenyl triflate 
• 41951-76-2 2-hydroxy-5-methoxybenzyl alcohol 
• 100-97-0 hexamethylenetetramine 
• 150-76-5 4-methoxy-phenol 
• 133503-46-5 1-(o-hydroxy-5-methoxyphenyl)-3-phenylpropargylic alcohol 
• 64-17-5 ethanol 
• 100-83-4 meta-hydroxybenzaldehyde 
• 591-31-1 3-methoxy-benzaldehyde 

Downstream Products

• 76322-07-1 2-ethoxycarbonylmethoxy-5-methoxybenzaldehyde 
• 93-02-7 2,5-dimethoxybenzaldehyde 
• 129503-20-4 methyl 2-(2-formyl-4-methoxyphenyloxymethyl)benzoate 
• 92210-61-2 6-methoxy-3-nitro-2H-1-benzopyran 
• 35467-98-2 (E)-4-methoxy-2-(2-nitrovinyl)phenol 
• 77055-97-1 N-(2-hydroxy-5-methoxy-benzyl)-serine 
• 90148-94-0 C₂₉H₃₃N₃O₆ 
• 30335-72-9 methoxy-5 nitro-2 benzofuranne 
• 117672-23-8 2-((Z)-2-Chloro-2-nitro-vinyl)-4-methoxy-phenol 
• 22927-97-5 6-methoxy-2,2-dimethyl-2H-chromene 
• 787-07-5 diethyl 1,4-cyclohexanedione-2,5-dicarboxylate 
• 21587-39-3 1-(5-methoxy-1-benzofuran-2-yl)ethan-1-one 
• 96829-79-7 ethyl 3-(5-methoxy-1-benzofuran-2-yl)-3-oxopropanoate 
• 95792-98-6 6-methoxy-3-nitro-2-(p-tolyl)-2H-chromene 

Relevant articles and documents

The first total syntheses of (±)-Preussomerins K and L using 2-arylacetal anion technology

The first syntheses of newly isolated members of the Preussomerin family, Preussomerins K and L, are reported. Key steps include the functionalisation of a 2-arylacetal anion, one-pot Friedel-Crafts cyclisation-deprotection and reductive opening of epoxides.

Enantioselective Cleavage of Cyclobutanols Through Ir-Catalyzed C?C Bond Activation: Mechanistic and Synthetic Aspects

The Ir-catalyzed conversion of prochiral tert-cyclobutanols to β-methyl-substituted ketones proceeds under comparably mild conditions in toluene (45–110 °C) and is particularly suited for the enantioselective desymmetrization of β-oxy-substituted substrates to give products with a quaternary chirality center with up to 95 % ee using DTBM-SegPhos as a chiral ligand. Deuteration experiments and kinetic isotope effect measurements revealed major mechanistic differences to related RhI-catalyzed transformations. Supported by DFT calculations we propose the initial formation of an IrIII hydride intermediate, which then undergoes a β-C elimination (C?C bond activation) prior to reductive C?H elimination. The computational model also allows the prediction of the stereochemical outcome. The Ir-catalyzed cyclobutanol cleavage is broadly applicable but fails for substrates bearing strongly coordinating groups. The method is of particular value for the stereo-controlled synthesis of substituted chromanes related to the tocopherols and other natural products.

Anchimerically Assisted Selective Cleavage of Acid-Labile Aryl Alkyl Ethers by Aluminum Triiodide and N, N-Dimethylformamide Dimethyl Acetal

Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.