methyl (2S)-2-(9H-fluoren-9-ylmethoxycarbonylamino)-3-hydroxypropanoate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from benzo[b]indeno[1,2-d]thiophen-6-ol (prepared by NaBH4 reduction of benzo[b]indeno[1,2-d]thiophen-9-one (Example i, Starting Fluorenones)) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester following method A, using trifluoroacetic acid as catalyst in place of H2SO4.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 1-phenyl-9H-fluoren-9-ol (prepared by NaBH4 reduction of 1-phenyl-9H-fluoren-9-one) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester following method A, using trifluoroacetic acid as catalyst in place of H2SO4 ; and

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: O-(9-t-butyl-9H-fluoren-9-yl)-L-serine: from 9-t-butyl-9H-fluoren-9-ol (Example 1x) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: O-[5-(4-Methylphenyl)-5H-dibenzo[a,d]cyclohepten-5-yl]-L-serine: from 5-(4-methylphenyl)-5H-dibenzo[a,d]cyclohepten-5-ol (Example it) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 9-cyclohexyl-9H-fluoren-9-ol (Example 1r) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 10,11-dihydro-5-(2-thienyl)-5H-dibenzo[a,d]cyclohepten-5-ol (Example 2d) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 9-(4-fluorophenyl)-9H-xanthen-9-ol (Example 1 m) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 9-(4-methylphenyl)-9H-xanthen-9-ol (Example 1q) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: from 9-(4-methylphenyl)-9H-thioxanthen-9-ol (Example 1p) and Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester;

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 0.17 g (0.5 mmol) Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester, 0.043 g (0.6 mmol) potassium carbonate and 0.083 g (0.5 mmol) potassium iodide in acetonitrile (2 mL) was added 0.16 g (0.5 mmol) of 9-bromo-9-phenyl-9H-fluorene (Aldrich), and the mixture stirred at 40° C. for 2 h. Filtration and removal of the solvent under vacuo gave the crude Nα -(9-fluorenylmethoxycarbonyl)-O-(9-phenyl-9H-fluoren-9-yl)-L-serine methyl ester which was subjected to the Fmoc deprotection in Step 2 without further purification. Filtration and removal of the solvent under vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 6.2 g (24 mmol) of 9-phenyl-9H-fluoren-9-ol (Example 1b) and 6.8 g (20 mmol) of Nα -(9-fluorenylmethoxycarbonyl)-L-serine methyl ester in benzene (150 mL) was placed in a round bottomed flask fitted with a Dean-Stark trap. Two drops of concentrated sulfuric acid were added and the mixture heated under reflux with stirring for 1 h. Removal of the solvent under vacuo gave the crude Nα -(9-fluorenylmethoxycarbonyl)--O--(9-phenyl-9H-fluoren-9-yl)-L-serine methyl ester which was subjected to the Fmoc deprotection in Step 2 without further purification. fitted with a Dean-Stark trap the mixture heated under reflux Removal of the solvent under vacuo