80715-22-6

Basic information

• Product Name: 4-Bromomethyl-5-methyl-1,3-dioxol-2-one
• Synonyms: 4-BROMOMETHYL-5-METHYL-1,3-DIOXOL-2-ONE;mdo-br;1,3-Dioxol-2-one, 4-(bromomethyl)-5-methyl;4-Bromomethyl-5-methyl-1.3-dioxolene-2-one;4-Bromomethyl-5-methyl-1,3-dio;4-methyl-5-bromo methyl-1,3-dioxol-2-one;4-BROMOMETHYL-5-METHYL-1,3-DIOXOL-2-ONE 90%;4-Bromomethyl-5-methyl-1,3-dioxocyclopenten-2-one
• CAS NO: 80715-22-6
• Molecular Formula: C₅H₅BrO₃
• Molecular Weight: 193
• EINECS: 1308068-626-2
• Mol File: 80715-22-6.mol
• Article Data: 31

Chemical Properties

• Boiling Point: 180.518 °C at 760 mmHg
• Flash Point: 62.976 °C
• Appearance: /
• Density: 1.742 g/cm³
• Vapor Pressure: 0.892mmHg at 25°C
• Refractive Index: 1.524
• CAS DataBase Reference: 4-Bromomethyl-5-methyl-1,3-dioxol-2-one(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Bromomethyl-5-methyl-1,3-dioxol-2-one(80715-22-6)
• EPA Substance Registry System: 4-Bromomethyl-5-methyl-1,3-dioxol-2-one(80715-22-6)

Safety Data

• Hazardous Substances Data: 80715-22-6(Hazardous Substances Data)

Usage

Chemical Properties

Liquid

InChI:InChI=1/C5H5BrO3/c1-3-4(2-6)9-5(7)8-3/h2H2,1H3

Synthetic route

4,5-Dimethyl-1,3-dioxole-2-one (37830-90-3) → 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6)

Conditions	Yield
With N-Bromosuccinimide; 2,2'-azobis(isobutyronitrile) In tetrachloromethane at 85℃; for 16h; Inert atmosphere;	95%
With N-Bromosuccinimide In chloroform Reflux; Large scale;	93.8%
With N-Bromosuccinimide; dibenzoyl peroxide In tetrachloromethane at 77℃; for 6h;	92%

4,5-Dimethyl-1,3-dioxole-2-one (37830-90-3) + a,a-azobisisobutyronitrile (AIBN) → 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6)

Conditions	Yield
With N-Bromosuccinimide In tetrachloromethane	90%

4-chloromethyl-5-methyl-1,3-dioxol-2-one (80841-78-7) → 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6)

Conditions	Yield
With sodium bromide In N,N-dimethyl-formamide at 20℃; for 1h;	75%
With sodium bromide In N,N-dimethyl-formamide at 20℃; for 1h;
With sodium bromide In N,N-dimethyl-formamide at 20℃; for 1.5h;
With sodium bromide In N,N-dimethyl-formamide; acetone at 40 - 45℃; for 5h; Product distribution / selectivity;

4,5-Dimethyl-1,3-dioxole-2-one (37830-90-3) + azobisisobutyronitrile (34241-39-9) → 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6)

Conditions	Yield
With N-Bromosuccinimide In tetrachloromethane	48%
With N-Bromosuccinimide In tetrachloromethane

N-Bromosuccinimide (128-08-5) + 4,5-Dimethyl-1,3-dioxole-2-one (37830-90-3) → 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6)

Conditions	Yield
2,2'-azobis(isobutyronitrile) In benzene at 20℃; for 0.5h; Heating / reflux;

5-[4'-(bromomethyl)[1,1'-biphenyl]-2-yl]-2-(triphenylmethyl)-1H-tetrazole + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + ethyl 4-(2-hydroxypropan-2-yl)-2-propyl-1H-imidazole-5-carboxylate (144689-93-0) → trityl olmesartan medoxomil (144690-92-6)

Conditions	Yield
Stage #1: 5-[4'-(bromomethyl)[1,1'-biphenyl]-2-yl]-2-(triphenylmethyl)-1H-tetrazole; ethyl 4-(2-hydroxypropan-2-yl)-2-propyl-1H-imidazole-5-carboxylate With tert-butylamine hydrobromide; potassium carbonate In acetone at 0 - 55℃; for 32h; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one With potassium carbonate; potassium iodide In acetone at 20 - 55℃; for 3h;	98.5%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + ulifloxacin (112984-60-8) → prulifloxacin (123447-62-1)

Conditions	Yield
With potassium hydrogencarbonate In N,N-dimethyl-formamide at 0℃; for 5h; Large scale;	95.4%
With potassium hydrogencarbonate In N,N-dimethyl-formamide for 5h; Ambient temperature;	62%
Stage #1: ulifloxacin With potassium hydrogencarbonate In acetonitrile at 25 - 30℃; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one at 15 - 30℃; for 27 - 28.25h;
Stage #1: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one; ulifloxacin With potassium hydrogencarbonate In N,N-dimethyl-formamide at 0 - 28℃; for 3 - 4h; Stage #2: With hydrogenchloride In chloroform; water for 0.25h; pH=0.8 - 1.0;
Stage #1: ulifloxacin With N-ethyl-N,N-diisopropylamine In acetonitrile at 20℃; for 0.166667h; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one In acetonitrile at 10 - 30℃; for 21h; Product distribution / selectivity;

(2S,3S)-3-((2-(2-chloro-5-trityl-5H-pyrrolo[2,3-b]pyrazin-7-yl)-5-fluoro-6-(thiophen-2-yl)pyrimidin-4-yl)amino)bicyclo[2.2.2]octane-2-carboxylic acid + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → (2S,3S)-(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl 3-((2-(2-chloro-5-trityl-5H-pyrrolo[2,3-b]pyrazin-7-yl)-5-fluoro-6-(thiophen-2-yl)pyrimidin-4-yl)amino)bicyclo[2.2.2]octane-2-carboxylate

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃;	95%

carbon dioxide (124-38-9) + L-phenylalanine (63-91-2) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → (S)-2-(5-Methyl-2-oxo-[1,3]dioxol-4-ylmethoxycarbonylamino)-3-phenyl-propionic acid 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl ester

Conditions	Yield
With caesium carbonate In N,N-dimethyl-formamide Ambient temperature;	94%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl iodide (80841-79-8)

Conditions	Yield
With potassium iodide In acetone Ambient temperature;	92%

carbon dioxide (124-38-9) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + benzyl-methyl-amine (103-67-3) → Benzyl-methyl-carbamic acid 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl ester

Conditions	Yield
With caesium carbonate In N,N-dimethyl-formamide Ambient temperature;	90%

2-(6-(4-(2-(tert-butyldimethylsilyloxy)ethyl)piperazin-1-yl)-2-methylpyrimidin-4-ylamino)-N-(2-chloro-6-methylphenyl)thiazole-5-carboxamide (881381-50-6) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → C33H44ClN7O5SSi (881381-64-2)

Conditions	Yield
With caesium carbonate In N,N-dimethyl-formamide at 20℃;	89%

6α,9α-difluoro-11β-hydroxy-16α,17α-isopropylidenedioxy-3-oxo-androsta-1,4-diene-17β-carbothioic acid (80474-38-0) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → 6α,9α-Difluoro-11β-hydroxy-16α,17α-isopropylidenedioxy-3-oxo-androsta-1,4-diene-17β-carbothioic acid S-(5-methyl-2-oxo-1,3-dioxol4-ylmethyl) ester

Conditions	Yield
With potassium carbonate In water; ethyl acetate; N,N-dimethyl-formamide	85%

4-(1-methoxy-1-methylethyl)-2-propyl-1-{4-(2-trityltetrazol-5-yl)phenyl}phenylmethylimidazole-5-carboxylic acid (1040405-55-7) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → 4-(1-methoxy-1-methylethyl)-2-propyl-1-{4-(2-trityltetrazol-5-yl)phenyl}phenylmethylimidazole-5-carboxylic acid-5-methyl-2-oxo-[1,3]-dioxolene-4-yl-methyl ester (1040405-56-8)

Conditions	Yield
With potassium carbonate In N,N-dimethyl acetamide at 20℃; for 5h;	84%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + azilsartan (147403-03-0) → C35H28N4O11

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 60℃; for 6h;	83%

formic acid (64-18-6) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → 4-formyloxymethyl-5-methyl-1,3-dioxolen-2-one (91526-17-9)

Conditions	Yield
With trimethylamine In acetonitrile at 20℃; for 1h;	82%
With triethylamine In acetonitrile for 1h; Ambient temperature;	80%
With triethylamine In acetonitrile for 2h; Ambient temperature;

3-[[(1S)-1-(dimethylcarbamoyl)propyl]-(trans-4-methylcyclohexanecarbonyl)amino]-5-(3-methylbut-1-ynyl)thiophene-2-carboxylic acid + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → C30H40N2O7S

Conditions	Yield
With potassium carbonate; sodium iodide In N,N-dimethyl-formamide at 80℃; for 0.333333h; Microwave irradiation;	78%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + methyl 2-ethoxy-1-((2′-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl)methyl)-1H-benzo[d]-imidazole-7-carboxylate (147403-52-9) → C31H26N4O8

Conditions	Yield
Stage #1: methyl 2-ethoxy-1-((2′-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl)methyl)-1H-benzo[d]-imidazole-7-carboxylate With potassium carbonate In N,N-dimethyl-formamide at -10 - 0℃; for 0.5h; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one In N,N-dimethyl-formamide at 20℃;	77.5%

5-(3,3-dimethylbut-1-ynyl)-3-[(trans-4-methylcyclohexanecarbonyl)-(2-oxo-2-thiomorpholino-ethyl)amino]thiophene-2-carboxylic acid + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → C30H38N2O8S

Conditions	Yield
With potassium carbonate; sodium iodide In N,N-dimethyl-formamide at 80℃; for 0.416667h; Microwave irradiation;	75%

5-(3-methylbut-1-ynyl)-3-[(trans-4-methylcyclohexanecarbonyl)-[(1S)-1-(morpholine-4-carbonyl)propyl]amino]thiophene-2-carboxylic acid. + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → C32H42N2O8S

Conditions	Yield
With potassium carbonate; sodium iodide In N,N-dimethyl-formamide at 80℃; for 0.333333h; Microwave irradiation;	74%

C28H40NO2P + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → C33H45BrNO5P

Conditions	Yield
In toluene at 130℃; for 21h; Inert atmosphere; Schlenk technique;	74%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + prulifloxacin (123447-62-1) → 6-Fluoro-1-methyl-7-[4-(5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl)-piperazin-1-yl]-4-oxo-4H-2-thia-8b-aza-cyclobuta[a]naphthalene-3-carboxylic acid 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl ester

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 39.9℃; for 3h;	72%
With N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 24.9℃; Rate constant; also in presence of DIPA and TNBA, var concn. of DMDO-Br and amines;

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + (S)-3-(((tert-butoxycarbonyl)amino)methyl)-5-methylhexanoic acid (649748-09-4) → (S)-3-(tert-butoxycarbonylamino-methyl)-5-methyl-hexanoic acid 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl ester (1026789-40-1)

Conditions	Yield
Stage #1: (S)-3-(((tert-butoxycarbonyl)amino)methyl)-5-methylhexanoic acid With caesium carbonate In methanol at 20℃; for 2h; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one In ISOPROPYLAMIDE	72%
Stage #1: (S)-3-(((tert-butoxycarbonyl)amino)methyl)-5-methylhexanoic acid With caesium carbonate In methanol at 20℃; for 2h; Stage #2: 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one In N,N-dimethyl acetamide	72%

carbon dioxide (124-38-9) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + benzylamine (100-46-9) → Benzyl-carbamic acid 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl ester

Conditions	Yield
With caesium carbonate In N,N-dimethyl-formamide Ambient temperature;	70%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + N-benzyloxycarbonyl NFLX (105439-94-9) → N-benzyloxycarbonyl NFLX (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester (105439-93-8)

Conditions	Yield
With potassium carbonate In acetonitrile at 60℃;	69%

5-Propyl-azepane-2-carboxylic acid [2-chloro-1-(3,4,5-trihydroxy-6-methylsulfanyl-tetrahydro-pyran-2-yl)-propyl]-amide + 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (96042-30-7) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → 1-(5-Methyl-2-oxo-[1,3]dioxol-4-ylmethyl)-5-propyl-azepane-2-carboxylic acid [2-chloro-1-(3,4,5-trihydroxy-6-methylsulfanyl-tetrahydro-pyran-2-yl)-propyl]-amide

Conditions	Yield
With potassium hydrogencarbonate In methanol; N,N-dimethyl-formamide	68%

tert-butyl 2-(methylamino)ethylcarbamate (122734-32-1) + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) → tert-butyl (2-(methyl((5-methyl-2-oxo-1,3-dioxol-4-yl)methyl)amino)ethyl)carbamate

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 16h;	67.4%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + ethyl 6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-(1,3)thiazeto(3,2-a)quinoline-3-carboxylate (113028-17-4) → ethyl 6-fluoro-1-methyl-7-<4-<(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl>-1-piperazyl>-4-oxo-4H-<1,3>thiazeto<3,2-a>-quinoline-3-carboxylate

Conditions	Yield
With potassium hydrogencarbonate In N,N-dimethyl-formamide for 1h; Ambient temperature;	66%
With potassium hydrogencarbonate In N,N-dimethyl-formamide

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (70458-96-7) → N-<(5-Methyl-2-oxo-1,3-dioxol-4-yl)methyl>norfloxacin (85195-76-2)

Conditions	Yield
With potassium hydrogencarbonate In N,N-dimethyl-formamide for 5h;	66%

potassium bicarbonate + 4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (70458-96-7) → N-<(5-Methyl-2-oxo-1,3-dioxol-4-yl)methyl>norfloxacin (85195-76-2)

Conditions	Yield
In N-methyl-acetamide; water	66%

4-bromomethyl-1,3-dioxa-5-methylcyclopentene-2-one (80715-22-6) + (-)-6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-<1,3>thiazeto<3,2-a>quinoline-3-carboxylic acid → S-(-)-6-fluoro-1-methyl-7-[4-(5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl-1-piperazinyl]-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid (1235993-71-1)

Conditions	Yield
With triethylamine In N,N-dimethyl-formamide at -5 - 5℃; for 3h; Product distribution / selectivity;	63%

Upstream product

• 80841-78-7 4-chloromethyl-5-methyl-1,3-dioxol-2-one 
• 37830-90-3 4,5-Dimethyl-1,3-dioxole-2-one 
• 34241-39-9 azobisisobutyronitrile 
• 128-08-5 N-Bromosuccinimide 

Downstream Products

• 100165-57-9 (5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl trans-4-<<(tert-butoxycarbonyl)amino>methyl>cyclohexanecarboxylate 
• 154750-06-8 (1,3-dioxa-5-methyl-cyclopentene-2-one-4-yl)methyl 4-ethyl-2-propyl-1-[[2'-(N-triphenylmethyl(tetrazol-5-yl))biphenyl-4-yl]methyl]imidazole-5-carboxylate 
• 859212-41-2 4-{4-[(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl]piperazin-1-ylmethyl}-3-trifluoromethyl-N-{4-methyl-3-[4-(5-pyrimidinyl)pyrimidin-2-ylamino]phenyl}benzamide 
• 123447-66-5 ethyl 6-fluoro-7-[4-(5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl-1-piperazinyl]-4-oxo-1-phenyl-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylate 
• 144689-63-4 olmesartan 
• 91526-18-0 4-hydroxymethyl-5-methyl-[1,3]dioxol-2-one 
• 157361-09-6 (5-Methyl-2-oxo-1,3-dioxolen-4-yl)methyl 4-{N-butyl-N-[(2'-[N-triphenylmethyl-1H-tetrazol-5-yl]biphenyl-4-yl)methyl]amino}pyrimidine-5-carboxylate 
• 91526-17-9 4-formyloxymethyl-5-methyl-1,3-dioxolen-2-one 
• 278793-42-3 C₂₇H₁₇Cl₃N₄O₇S 
• 681424-47-5 (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl exo-(1R,5S)-3-[4-((5S)-5-{[(difluoroacetyl)amino]methyl}-2-oxo-1,3-oxazolidin-3-yl)-2,6-difluorophenyl]-3-azabicyclo[3.1.0]hexane-6-carboxylate 
• 681424-43-1 (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl exo-(1R,5S)-3-[4-((5S)-5-{[(dichloroacetyl)amino]methyl}-2-oxo-1,3-oxazolidin-3-yl)-2,6-difluorophenyl]-3-azabicyclo[3.1.0]hexane-6-carboxylate 
• 524070-84-6 (5-methyl-2-oxo-1,3-dioxol-4-yl)-methyl (5R,6S)-6-[(1R)-1-hydroxyethyl]-3-[3-(hydroxymethyl)-phenyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate 
• 80734-02-7 ampicillin (5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl ester hydrochloride 
• 100165-54-6 (5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl trans-4-(aminomethyl)cyclohexanecarboxylate hydrochloride 

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