2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

• 9,9-Dioctyl-2,7-bis(4,4,5,5-tetramethyl1,3,2-dioxaborolane-2-yl)dibenzosilole.
• 3,9-Bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,11-di(1-decylundecyl)indolo[3,2-b]carbazole.
• 2,7-Bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-dioctylfluorene.
• 2,7-Bis(4′,4′,5′,5′-tetramethyl-1′,3′,2′-dioxaborolan-2′-yl)-N-9′′-heptadecanylcarbazole.

76-09-5

5419-55-6

61676-62-8

Step c) Preparation of isopropyl pinacol borate: triisopropyl borate (261.0 g, 1.388 mol) and pinacol (142.5 g, 1.207 mol) were added to a 20 L four-necked flask, and the mixture was heated to about 90 °C and maintained for 12 to 16 hours. The progress of the reaction was monitored by gas chromatography (GC), and the completion of the reaction was measured by a pinacol content of less than 4.0%. Upon completion of the reaction, a distillation operation was performed to collect fractions with boiling points between 174 and 178 °C to obtain the target product isopropanol pinacol borate as a colorless oil. Yields ranged from 80-90% in six 20 L batches of the operation.GC analysis showed a product purity of 87-96%, while 1H NMR analysis indicated an extremely high product purity. [The difference between GC purity and 1H NMR purity is attributed to the instability of the product under GC conditions].