137076-54-1, 2-(4,7,10-Tris(2-(tert-butoxy)-2-oxoethyl)-1,4,7,10-tetraazacyclododecan-1-yl)acetic acid is a catalyst-ligand compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated
The product of Part 17B (131 mg, 0.250 mmol) was dissolved in 2:1 MeCN/H2O (5.00 mL) and successively treated with 14.2 mg TPPTS (25.0 mumol; 10 mol %), Et2NH (129 muL, 1.25 mmol) and 2.8 mg Pd(OAc)2 (12.5 mumol; 5 mol %) at 22 C. Complete deprotection was observed within 0.25 h. The resulting amber solution was then lyophilized to remove all volatile components. The solids thus obtained were redissolved in DMF and successively treated with HOBt (45.9 mg, 0.300 mmol), 2-(1,4,7,10-tetraaza-4,7,10-tris{[(tert-butyl)oxycarbonyl]methyl}-cyclododecyl)acetic acid (172 mg, 0.300 mmol), i-Pr2NEt (105 muL, 0.600 mmol) and HBTU (114 mg, 0.300 mmol) at 22 C. After 0.25 h, complete acylation was observed; only trace amounts of regioisomeric and dimeric products formed. The resulting solution was partitioned between EtOAc and H2O (50 mL each) with transfer to a separatory funnel. The layers separated and the aqueous layer washed with EtOAc (2¡Á50 mL). The EtOAc solution was further washed with 0.1 M NaOH (3¡Á50 mL) and saturated aqueous NaCl (3¡Á50 mL each), then dried over MgSO4, filtered and concentrated in vacuo to a pale yellow oil that was used without further purification in the subsequent deprotection step. The protected conjugate (0.250 mmol theoretical) was dissolved in dioxane (2.50 mL) then successively treated with H2O (23 muL) and HCl (10.0 mmol; 2.50 mL of a 4 M solution in dioxane) at 22 C. The resulting pale yellow solution was stirred 17 h, during which time a heavy white precipitate formed. Upon complete deprotection, the volatiles were removed under a stream of N2 and the white solid residue redissolved in H2O containing 0.1% TFA (8.00 mL) then partially purified by HPLC on a Phenomenex Luna C18 column (21.2¡Á250 mm) using a 2%/min gradient from 0-60% MeCN containing 0.1% TFA and 10% H2O at 20 mL/min. The main product peak eluting at 21 min was collected and lyophilized to a white powder. Final purification was performed using the identical column and method. The main product peak was collected and lyophilized to a white powder (0.110 g, 97.3 mumol; 38.9%).
As the paragraph descriping shows that 137076-54-1 is playing an increasingly important role.
Reference£º
Patent; Lantheus Medical Imaging, Inc.; Cesati, Richard R.; Harris, Thomas D.; Robinson, Simon P.; Looby, Richard J.; Cheesman, Edward H.; Yalamanchili, Padmaja; Casebier, David S.; (86 pag.)US9266846; (2016); B2;,
Metal catalyst and ligand design
Ligand Template Strategies for Catalyst Encapsulation – NCBI