8.51087

PyClock

6-Chloro-benzotriazole-1-yloxy-tris-pyrrolidinophosphonium hexafluorophosphate Novabiochem^®

• Synonym(s): PyClock, 6-Chloro-benzotriazole-1-yloxy-tris-pyrrolidinophosphonium hexafluorophosphate
• Empirical Formula (Hill Notation): C₁₈H₂₇ClF₆N₆OP₂
• CAS Number: 893413-42-8
• Molecular Weight: 554.84
• MDL number: MFCD14560589
• UNSPSC Code: 12352107
• NACRES: NA.22

Properties

• Quality Level: 200
• product line: Novabiochem^®
• assay: ≥98.0% (HPLC)
• form: powder
• reaction suitability: reaction type: Coupling Reactions
• manufacturer/tradename: Novabiochem^®
• mp: 165-175 °C
• application(s): peptide synthesis
• storage temp.: 2-8°C
• InChI: 1S/C18H27ClN6OP.F6P/c19-16-7-8-17-18(15-16)25(21-20-17)26-27(22-9-1-2-10-22,23-11-3-4-12-23)24-13-5-6-14-24;1-7(2,3,4,5)6/h7-8,15H,1-6,9-14H2;/q+1;-1
• InChI key: QJZCQEPNBRAYQL-UHFFFAOYSA-N

Description

General description

PyClocK is the 6-chloro analog of PyBOP. Reaction of protected amino acids with PyClocK in the presence of base generates the corresponding 6-chloro-1-benzotriazolyl (Cl-OBt) ester. These active esters are considerably more reactive than those produced when using PyBOP or HBTU, owing to 6-chloro-1-hydroxybenzotriazole (Cl-HOBt) being more acidic than HOBt. PyClocK is an excellent coupling reagent for situations where carboxyl activation may be sluggish, such as cyclizations and fragment condensations, as unlike imminium-based reagents such as HBTU and HATU excess PyClocK cannot cause end-capping of peptide chains.


Associated Protocols and Technical Articles
Guide to Selection of Coupling Reagents

Analysis Note

Color (visual): white to slight yellow to beige
Appearance of substance (visual): powder
Identity (IR): conforms
Assay (HPLC, area%): ≥ 98.0 % (a/a)
Solubility (5% in NMP (1-Methyl-2-pyrrolidone)): clear

Legal Information

Novabiochem is a registered trademark of Merck KGaA, Darmstadt, Germany

Safety Information

• pictograms: GHS07
• signalword: Warning
• hcodes: H315 - H319 - H335
• pcodes: P261 - P264 - P271 - P280 - P302 + P352 - P305 + P351 + P338
• Hazard Classifications: Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3
• target_organs: Respiratory system
• Storage Class: 11 - Combustible Solids
• wgk_germany: WGK 3
• flash_point_f: Not applicable
• flash_point_c: Not applicable