Carborhodamine compounds and methods of preparation thereof

A method for preparing carborhodamine compounds having a structure of

• comprising reacting a compound having a structure of
• with a compound having a structure of
• in a reaction mixture comprising a solvent and a Lewis acid,
• wherein:
• R1 and R2 are independently (C1-C20)alkyl or (C1-C20)heteroalkyl, or together R1 and R2 form a ring structure comprising one or more rings,
• R3, R6, R7, and R10 are independently selected from H, (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkenyl, (C1-C20)alkynyl, aryl, heteroaryl, a linking group, halo, —OR′, —OC(O)R′, —NR′R″, —SR′, —OC(O) NR′R″, —NR″C(O)R′, —NR″C(O)OR′, —NR′C(O)NR″R′″, and —SO2H, wherein R′, R″ and R′″ are independently selected from H, (C1-C8)alkyl, (C1-C8)heteroalkyl, aryl, heteroaryl and a linking group, and wherein (C1-C20)alkyl, aryl, and heteroaryl groups are unsubstituted or substituted,
• R4, R5, R8 and R9 are independently selected from H, (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkenyl, (C1-C20)alkynyl, aryl, heteroaryl, and a linking group, wherein (C1-C20)alkyl, aryl, and heteroaryl groups are unsubstituted or substituted,
• or
• R3, R4, R5, R6, R7, R8, R9, and R10 form one or more 4- to 7-member ring systems by bridging between one or more of R3, R4, R5, R6, R7, R8, R9, and R10,
• R11, R12, R13 and R14 are independently selected from H, (C1-C20)alkyl, (C1-C20)alkoxy, (C1-C20)alkenyl, (C1-C20)alkynyl, aryl, heteroaryl, a linking group, halo, —ORiv, —OSO2Riv, —OC(O) Riv, —NRivRv, —SRiv, —Riv, —CN, —NO2, —CO2Riv, —CONRivRv, —C(O) Riv, —SO2Riv, —SO2NRivRv, —N3, —CH(Ph)2, perfluoro(C1-C4)alkoxy, and perfluoro(C1-C4)alkyl, wherein Ph is phenyl, wherein Riv and Rv are independently selected from H, (C1-C20)alkyl perfluoro(C1-C4)alkyl, perfluoro(C1-C4)heteroalkyl, aryl and heteroaryl, and wherein aryl and heteroaryl groups are unsubstituted or substituted,
• or
• R11, R12, R13 and R14 form one or more 4- to 7-member ring systems by bridging between one or more of R11, R12, R13 and R14, and
• the linking group is selected from (C1-C20)alkyl, aryl, (C1-C20)heteroalkyl, heteroaryl and combinations thereof, wherein at least one hydrocarbon hydrogen of the linking group is replaced with a protected or unprotected carboxyl or a hydroxyl group.