Solid forms of a cdk2 inhibitor

A crystalline solid form of the free base of Compound (1), wherein the crystalline solid form is referred to as crystalline solid Form A and is characterized by an XRPD pattern comprising three, four, or five peaks at the diffraction angles (2θ) selected from the group consisting of 5.9°±0.2, 17.6°±0.2, 21.4°±0.2, 25.1°±0.2, and 27.3°±0.2.

A crystalline solid form of the free base of Compound (I), wherein Compound (I) is represented by the following structural formula:

• wherein the crystalline solid form is referred to as crystalline solid Form B and is characterized by an XRPD pattern comprising three, four, or five peaks at the diffraction angles (2θ) selected from the group consisting of 5.8°±0.2, 14.9°±0.2, 17.3°±0.2, 23.9°±0.2, and 24.6°±0.2.

A crystalline solid form of the free base of Compound (I), wherein the crystalline solid form is referred to as crystalline solid Form B and is characterized by an XRPD pattern comprising three, four, or five peaks at the diffraction angles (2θ) selected from the group consisting of 5.8°±0.2, 17.3°±0.2, 21.5°±0.2, 25.3°±0.2, and 29.1°±0.2.

A crystalline solid form of the free base of Compound (I) represented by the following structural formula:

• wherein the crystalline solid form is referred to as crystalline solid Form C and is characterized by an XRPD pattern comprising three, four, five, or six peaks at the diffraction angles (2θ) selected from the group consisting of 8.7°±0.2, 10.6°±0.2, 13.4°±0.2, 15.3°±0.2, 19.0°±0.2, and 25.8°±0.2.

An amorphous form of the free base of Compound (I) represented by the following structural formula:

A crystalline solid form of a pharmaceutically acceptable salt of Compound (I) represented by the following structural formula:

• wherein the salt is selected from the group consisting of a methanesulfonate salt, an ethanesulfonate salt, a benzenesulfonate salt, a tosylate salt, a naphthalene-2-sulfonate salt, a glycine salt, a succinate salt, a citrate salt, a tartrate salt, an adipate salt, an aspartate salt, a histidine salt, a vanillin salt, a phosphate salt, a hydrochloride salt, a hydrobromide salt, a nitrate salt, and a sulfate salt.

A method of preparing Compound (I):

• comprising reacting a first compound represented by formula (1):
• and a second compound represented by formula (2):
• wherein reacting the first and second compound further includes a base that activates the diamine compound (2) that then reacts with the heteroaryl chloride compound (1).