{
	"@odata.context": "http://portal.xpertdoc.com/odata4/v6/$metadata#Documents/$entity",
	"DocumentId": "00000000-0000-0000-0000-000000000000",
	"BatchId": "00000000-0000-0000-0000-000000000000",
	"SequenceNumber": 0,
	"Status": "Completed",
	"StartTime": "2016-01-01T00:00:00.0000000Z",
	"EndTime": "2016-01-01T00:00:00.0000000Z",
	"InputDocumentName": "Document.docx",
	"InputDocumentType": "Docx",
	"InputMetadata": null,
	"OutputDocumentName": "Document.pdf",
	"OutputDocumentType": "Pdf",
	"OutputMetadata": null,
	"ErrorMessage": null,
	"CreatedByUserProfileId": "00000000-0000-0000-0000-000000000000",
	"CreatedDate": "2016-01-01T00:00:00.0000000Z",
	"ModifiedByUserProfileId": "00000000-0000-0000-0000-000000000000",
	"ModifiedDate": "2016-01-01T00:00:00.0000000Z",
	"Timestamp": "AAAAAAAAQT0="
}

var document = portalContext.Documents.Where(d => d.DocumentId == Guid.Parse("00000000-0000-0000-0000-000000000000")).FirstOrDefault();	

document.Name = "New Name";
document.ValueToChange = value;

portalContext.UpdateObject(document);
portalContext.SaveChanges();