All air-or moisture-sensitive reactions were performed under positive pressure of nitrogen with oven-dried glassware. Anhydrous solvents or reagents such as dichloromethane, N,Ndimethylformamide (DMF), acetonitrile, methanol, and triethylamine were purchased from Sigma-Aldrich. To follow most chemical reactions LC/MS of reaction aliquots were analyzed using a gradient of 4% to 100% acetonitrile (containing 0.025% trifluoroacetic acid) and water (containing 0.05% trifluoroacetic acid) with a 4.5-minute run time at a flow rate of 1 mL/min in an Agilent Extend-C18 column (3.5 micron, 4.6 x 100 mm) at a temperature of 50 °C using an Agilent Diode Array Detector. Confirmation of molecular formulae was accomplished using electrospray ionization in the positive mode with the Agilent Masshunter software (version B.02).